We present HST spectroscopy for 45 cataclysmic variables (CVs), observed with HST/COS and HST/STIS. For 36 CVs, the white dwarf is recognisable through its broad Ly α absorption profile and we measure the white dwarf effective temperatures (T eff ) by fitting the HST data assuming log g = 8.35, which corresponds to the average mass for CV white dwarfs ( 0.8 M ). Our results nearly double the number of CV white dwarfs with an accurate temperature measurement. We find that CVs above the period gap have, on average, higher temperatures ( T eff 23 000 K) and exhibit much more scatter compared to those below the gap ( T eff 15 000 K). While this behaviour broadly agrees with theoretical predictions, some discrepancies are present: (i) all our new measurements above the gap are characterized by lower temperatures (T eff 16 000-26 000 K) than predicted by the present-day CV population models (T eff 38 000-43 000 K); (ii) our results below the gap are not clustered in the predicted narrow track and exhibit in particular a relatively large spread near the period minimum, which may point to some shortcomings in the CV evolutionary models. Finally, in the standard model of CV evolution, reaching the minimum period, CVs are expected to evolve back towards longer periods with mean accretion ratesṀ 2 × 10 −11 M yr −1 , corresponding to T eff 11 500 K. We do not unambiguously identify any such system in our survey, suggesting that this major component of the predicted CV population still remains elusive to observations.

Clinical leadership has been acclaimed widely as a major factor influencing the quality of patient care but research has revealed a paucity of preparation for this significant role. Leadership literature has rarely addressed clinical leadership specifically or referred to the difficulties in characterizing effective clinical leaders. The research informing this paper focused on clinical leadership and identified five attributes of effective clinical leaders: creativity, highlighting, influencing, respecting, and supporting. Effective clinical leaders adopted a transformational leadership style and improved care, through others, by including transformational (soft) knowledge as an integral part of their effective practice repertoire. Phronesis is introduced as practical wisdom that is gained through immersion in relevant experience, and as an essential element of preparation for clinical nursing leadership practice. It is argued, that learning to transform care requires opportunities to work within an environment that engenders and supports aspiring leaders. The paper describes the research process, elucidates the attributes through illustrative examples from the research data, and discusses an emergent educational strategy for the development of these attributes by clinicians in their practice environments. The paper also describes the application of this research through an interdisciplinary programme for staff leading teams in both health and social services sectors.

Lyme borreliosis is increasing rapidly in many parts of the world and is the most commonly occurring vector-borne disease in Europe and the USA. The disease is transmitted by ticks of the genus Ixodes. They require a blood meal at each stage of their life cycle and feed on a wide variety of wild and domestic animals as well as birds and reptiles. Transmission to humans is incidental and can occur during visits to a vector habitat, when host mammals and their associated ticks migrate into the urban environment, or when companion animals bring ticks into areas of human habitation. It is frequently stated that the risk of infection is very low if the tick is removed within 24–48 hours, with some claims that there is no risk if an attached tick is removed within 24 hours or 48 hours. A literature review has determined that in animal models, transmission can occur in <16 hours, and the minimum attachment time for transmission of infection has never been established. Mechanisms for early transmission of spirochetes have been proposed based on their presence in different organs of the tick. Studies have found systemic infection and the presence of spirochetes in the tick salivary glands prior to feeding, which could result in cases of rapid transmission. Also, there is evidence that spirochete transmission times and virulence depend upon the tick and Borrelia species. These factors support anecdotal evidence that Borrelia infection can occur in humans within a short time after tick attachment.

The results imply that to enhance clinical nursing, leadership factors that enable and constrain clinical nursing leadership have to be identified and acted upon by individuals and those who they report to professionally.

Students prepared for classroom examinations by completing practice tests, with selected items from these practice tests repeated, in either the original or in a modified wording, on classroom examinations and a final examination. The availability of immediate self-corrective feedback on Study 1 practice tests (0, 3, or 6 practice tests) was varied , while in Study 2, the timing of feedback provided during practice tests (immediate, end of test, 24-hour delay, control) was varied . Performance on examinations was elevated by the provision of immediate feedback on practice tests in both studies, especially when test items were presented in their original wording, with some generalization observed on items presented in a modified wording. Predictions made in accordance with the interference-perseveration hypothesis and the delayretention effect were not supported. These results demonstrate considerable potential for immediate self-corrective feedback, delivered during test preparation through the Immediate Feedback Assessment Technique, to enhance performance on classroom examinations and to promote the retention of factual information during the academic semester.

The purpose of this work was to explore clinical nursing leadership. The research was based on a critical examination of the leadership themes derived from the nursing literature of the United Kingdom, the United States of America and Australia, between 1992 and 1997. The work was also influenced by the findings from semistructured interviews undertaken with five clinical leaders in nursing from the United Kingdom, and study tours to both the United States of America and Australia. The findings support a proposed leadership model as a basis for further exploration and as a framework for contemplating clinical leadership and leadership preparation. A model is presented that identifies factors which influence leadership styles, such as external environment, internal environment, experience and understanding. Four leadership styles are outlined: transactional, transformational, connective and renaissance. These leadership styles are linked to nursing care approaches. A second model provides a basis for considering power and its impact in the workplace. Based on these findings, the contents of a leadership preparation course are outlined.

We propose and test a scenario for the assembly and evolution of luminous matter in galaxies which substantially differs from that adopted by other semi-analytic models. As for the dark matter, we follow the detailed evolution of haloes within the canonical cold dark matter cosmology using standard Monte Carlo methods. However, when overlaying prescriptions for baryon evolution, we take into account an effect pointed out in the past few years by a number of studies mostly based on intensive N-body simulations, namely that typical halo growth occurs in two phases: an early, fast collapse phase featuring several major merger events, followed by a late, quiescent accretion on to the halo outskirts. We propose that the two modes of halo growth drive two distinct modes for the evolution of baryonic matter, favouring the development of the spheroidal and disc components of galaxies, respectively. We test this idea using the semi-analytic technique. Our galaxy formation model envisages an early coevolution of spheroids and the central supermassive black holes, already tested in our previous works, followed by a relatively quiescent growth of discs around the preformed spheroids. In this exploratory study, we couple our model with the spectrophotometric code GRASIL, and compare our results on several properties of the local galaxy population with observations, finding an encouraging agreement.

The clinical diagnosis of Lyme borreliosis can be supported by various test methodologies; test kits are available from many manufacturers. Literature searches were carried out to identify studies that reported characteristics of the test kits. Of 50 searched studies, 18 were included where the tests were commercially available and samples were proven to be positive using serology testing, evidence of an erythema migrans rash, and/or culture. Additional requirements were a test specificity of ≥85% and publication in the last 20 years. The weighted mean sensitivity for all tests and for all samples was 59.5%. Individual study means varied from 30.6% to 86.2%. Sensitivity for each test technology varied from 62.4% for Western blot kits, and 62.3% for enzyme-linked immunosorbent assay tests, to 53.9% for synthetic C6 peptide ELISA tests and 53.7% when the two-tier methodology was used. Test sensitivity increased as dissemination of the pathogen affected different organs; however, the absence of data on the time from infection to serological testing and the lack of standard definitions for “early” and “late” disease prevented analysis of test sensitivity versus time of infection. The lack of standardization of the definitions of disease stage and the possibility of retrospective selection bias prevented clear evaluation of test sensitivity by “stage”. The sensitivity for samples classified as acute disease was 35.4%, with a corresponding sensitivity of 64.5% for samples from patients defined as convalescent. Regression analysis demonstrated an improvement of 4% in test sensitivity over the 20-year study period. The studies did not provide data to indicate the sensitivity of tests used in a clinical setting since the effect of recent use of antibiotics or steroids or other factors affecting antibody response was not factored in. The tests were developed for only specific Borrelia species; sensitivities for other species could not be calculated.