The dynamics of a ringing church bell

Church bell ringing as practised in the UK involves large-amplitude motions of both bell and clapper. A simulation model is developed and validated against experimental measurements. It is shown that the clapper does not hit the bell with a single impact but a long series of bounces, and this has important consequences for the decay profile of the bell vibration. Information relevant to bell-ringers and bell-hangers is collected in a series of design charts derived from the simulation model. These charts can assist in the diagnosis and correction of faults. Arising from the analysis of the bouncing clapper, a more general result is also presented relating to the frequency bandwidth when any structure is excited by a small bouncing impactor, for example an impulse hammer used in vibration testing.Peer Reviewe

Factors associated with testicular self-examination among unaffected men from multiple-case testicular cancer families

<p>Abstract</p> <p>Background</p> <p>The lifetime testicular cancer (TC) risk in the general population is relatively low (~1 in 250), but men with a family history of TC are at 4 to 9 times greater risk than those without. Some health and professional organizations recommend consideration of testicular self-examination (TSE) for certain high-risk groups (e.g. men with a family history of TC). Yet little is known about factors associated with TSE behaviors in this at-risk group.</p> <p>Methods</p> <p>We collected information on this subject during an on-going NCI multidisciplinary, etiologically-focused, cross-sectional Familial Testicular Cancer (FTC) study. We present the first report specifically targeting TSE behaviors among first- and second-degree relatives (n = 99) of affected men from families with ≥ 2 TC cases. Demographic, medical, knowledge, health belief, and psychological factors consistent with the Health Belief Model (HBM) were evaluated as variables related to TSE behavior, using chi-square tests of association for categorical variables, and t-tests for continuous variables.</p> <p>Results</p> <p>For men in our sample, 46% (n = 46) reported performing TSE regularly and 51% (n = 50) reported not regularly performing TSE. Factors associated (p < .05) with regularly performing TSE in multivariate analysis were physician recommendation and testicular cancer worry. This is the first study to examine TSE in unaffected men from FTC families.</p> <p>Conclusion</p> <p>The findings suggest that, even in this high-risk setting, TSE practices are sub-optimal. Our data provide a basis for further exploring psychosocial issues that are specific to men with a family history of TC, and formulating intervention strategies aimed at improving adherence to TSE guidelines.</p

Are Reports of Psychological Stress Higher in Occupational Studies? A Systematic Review across Occupational and Population Based Studies

This study was funded by the UK Ministry of Defence (MoD)

Joint strategic planning between health and local authorities

This paper describes an approach to joint consideration of strategic planning problems between Health Authorities and Local Authorities. It is currently being pilot tested in the UK by two Area Health Authorities and their corresponding County Councils. The approach is most effective in planning the provision of health and social services for periods between three and ten years ahead and has been particularly designed for planning the non-acute services. These are the services for which joint planning between the health and social services is most important. Depending on local needs and planning priorities the approach may be used for one or more 'client groups' (the Elderly, Mentally Ill, Mentally Handicapped, Physically Handicapped etc.). In the pilot applications the approach is being used in planning for the Elderly client group only. The model now used relies on very simple assumptions, arithmetic calculations, and a heuristic optimisation algorithm, in place of a previous mathematical programming model originally aimed at national planning needs and then adapted to local planning. The revised model has achieved these simplifications, while extending the power of the model to fit local needs, by separating out different parts of the problem corresponding to different stages in the planning process, and developing techniques appropriate to each. In a companion paper2 in this issue authors from the participating Authorities put their views on the pilot applications of the approach.