Quantised vortices and mutual friction in relativistic superfluids

We consider the detailed dynamics of an array of quantised superfluid vortices in the framework of general relativity, as required for quantitative modelling of realistic neutron star cores. Our model builds on the variational approach to relativistic (multi-) fluid dynamics, where the vorticity plays a central role. The description provides a natural extension of, and as it happens a better insight into, existing Newtonian models. In particular, we account for the mutual friction associated with scattering of a second "normal" component in the mixture off of the superfluid vortices.Comment: 9 pages, RevTe

Origins and current issues in Quiet Eye research

All sports require precise control of physical actions and vision is essential in providing the information the movement systems needs to perform at a high level. Vision and focus of attention play a critically important role as the ability to direct the gaze to optimal areas in the playing environment, at the appropriate time, is central to success in all sports. One variable that has been consistently found to discriminate elite performers from their near-elite and novice counterparts is the Quiet Eye (QE). In the present paper, I first define the QE, followed by an explanation of its origins as well as the question: why have I pursued this one variable for over 35 years? I then provide a brief overview of QE research, and concentrate on QE training, which has emerged as an effective method for improving both attentional focus and motor performance. In the final section, I discuss some future directions, in particular those related to identifying the neural networks underlying the QE during successful trials

The Quiet Eye: Reply to sixteen commentaries

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Reducing DCO registrations through electronic matching of cancer registry data and routine hospital data

The Thames Cancer Registry (TCR) has registered a high proportion of tumours from death certificate information only (DCO) registrations. This paper describes the results of a study set up to establish whether this proportion could be reduced by linking cancer registrations with routine hospital data from the Hospital Episodes Statistics (HES) data set using computerized matching. A total of 67 752 registrations were identified from the TCR. Matches were found in the HES data set for 66%. The proportion of cases retrieved for each tumour site was: 72% for colorectal cancer; 62% for cancer of the lung, trachea or bronchus; and 65% for female breast cancer. For all three tumour sites the proportion of matches found for patients registered from hospital case notes was higher than the proportion found for patients registered as DCOs (P< 0.0001 for all three tumour sites). Among matched DCO cases, 58% had at least one procedure recorded. DCO rates might be reduced by as much as 43% (from 17% of total registrations to less than 10%) for the three most common cancers if the method of electronic matching outlined here was used. Younger age groups, prognosis of tumour site and residence in North Thames region were all positively associated with successful matching (P< 0.0001 in all three cases). Many matched DCO cases were found to have had more than one admission for cancer. Among ordinary in-patient admissions, admissions to patients ratios of 1.5, 1.4 and 1.9 were found for colorectal, lung and breast cancers respectively. Of 5190 matched DCOs a procedure was recorded for 3013 (58%). HES data offer a useful aid to follow-up of case notes on patients identified to the registry by death certificates. Doubts about the completeness and accuracy of HES data mean case notes must remain the ‘gold standard’. © 2000 Cancer Research Campaig

ABO(H) blood groups and vascular disease: a systematic review and meta-analysis

&lt;i&gt;Background&lt;/i&gt;: Associations between vascular disease and ABO(H) blood groups have a long history, but no consensus exists regarding its magnitude and significance, or whether it relates to all disorders equally. An accurate calculation of risk would allow direct assessment of whether the effects of non-O status on thrombosis risk are of the magnitude predicted by its effect on von Willebrand factor/FVIII levels. &lt;i&gt;Methods&lt;/i&gt; &lt;i&gt;and&lt;/i&gt; &lt;i&gt;results&lt;/i&gt;: We conducted a systematic review and meta-analysis of studies reporting associations with non-O blood groups. This gave pooled odds ratios of 1.25 [95% confidence interval (CI) 1.14–1.36] for myocardial infarction (MI), 1.03 (95% CI 0.89–1.19) for angina, 1.45 (95% CI 1.35–1.56) for peripheral vascular disease, 1.14 (95% CI 1.01–1.27) for cerebral ischemia of arterial origin, and 1.79 (95% CI 1.56 to 2.05) for venous thromboembolism (VTE). However, restriction to prospective MI studies only did not confirm the association (OR 1.01; 95% CI 0.84–1.23), although these studies may have failed to capture early-onset disease. For VTE, using a combined group of OO/A&lt;sub&gt;2&lt;/sub&gt;A&lt;sub&gt;2&lt;/sub&gt;/A&lt;sub&gt;2&lt;/sub&gt;O as index, the combination of A&lt;sub&gt;1&lt;/sub&gt;A&lt;sub&gt;1&lt;/sub&gt;/A&lt;sub&gt;1&lt;/sub&gt;B/BB gave an OR of 2.44 (95% CI 1.79–3.33) and A&lt;sub&gt;1&lt;/sub&gt;O/ BO/A&lt;sub&gt;2&lt;/sub&gt;B an OR of 2.11 (95% CI 1.66–2.68). &lt;i&gt;Conclusions&lt;/i&gt;: This study confirms the historical impression of linkage between some vascular disorders and non-O blood group status. Although the odds ratios are similar to those predicted by the effect of ABO(H) on von Willebrand factor levels, further work is required to assess risk prospectively and to refine the effect of reducing O(H) antigen expression on thrombosis. However, as non-O and particularly A&lt;sub&gt;1&lt;/sub&gt;A&lt;sub&gt;1&lt;/sub&gt;, A&lt;sub&gt;1&lt;/sub&gt;B, BB constitute a significant proportion of the population attributable fraction of VTE, there may be a role for more widespread adoption of ABO(H) typing in testing strategies

Community rotorcraft air transportation benefits and opportunities

Information about rotorcraft that will assist community planners in assessing and planning for the use of rotorcraft transportation in their communities is provided. Information useful to helicopter researchers, manufacturers, and operators concerning helicopter opportunities and benefits is also given. Three primary topics are discussed: the current status and future projections of rotorcraft technology, and the comparison of that technology with other transportation vehicles; the community benefits of promising rotorcraft transportation opportunities; and the integration and interfacing considerations between rotorcraft and other transportation vehicles. Helicopter applications in a number of business and public service fields are examined in various geographical settings