3,889 research outputs found

    Flattening Functions on Flowers

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    Let TT be an orientation-preserving Lipschitz expanding map of the circle \T. A pre-image selector is a map \tau:\T\to\T with finitely many discontinuities, each of which is a jump discontinuity, and such that τ(x)∈T−1(x)\tau(x)\in T^{-1}(x) for all x\in\T. The closure of the image of a pre-image selector is called a flower, and a flower with pp connected components is called a pp-flower. We say that a real-valued Lipschitz function can be Lipschitz flattened on a flower whenever it is Lipschitz cohomologous to a constant on that flower. The space of Lipschitz functions which can be flattened on a given pp-flower is shown to be of codimension pp in the space of all Lipschitz functions, and the linear constraints determining this subspace are derived explicitly. If a Lipschitz function ff has a maximizing measure SS which is Sturmian (i.e. is carried by a 1-flower), it is shown that ff can be Lipschitz flattened on some 1-flower carrying SS.Comment: Accepted for publication and confirmed for december 200

    The impact of a new regional air ambulance service on a large general hospital

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    Background: Helicopter air ambulance crews are influenced in their selection of the destination hospital for their patients by several factors including: distance from the scene; facilities, on site specialties, and senior cover of the receiving hospital; and the proximity of the helicopter landing area to the emergency department (ED). Only a limited number of hospitals have landing sites adjacent to the ED from which patients can be taken directly into the department (primary landing sites). Helicopter crews will often elect to over fly hospitals that do not have primary landing sites because secondary land transfers will add delays in delivering patients. Birmingham Heartlands Hospital has an elevated helideck adjacent to the ED. In October 2003, the Warwickshire and Northamptonshire Air Ambulance (WNAA) service was launched; the hospital sits on the western periphery of the area served by the service. Methods: Prospective data was collated on all patients brought by WNAA to Heartlands Hospital between 1 October 2003 and 31 August 2004. Results: In the 10 month period after the launch of the service, the helicopter delivered 83 patients to the ED; 74 of these were "off patch". This additional workload generated 163 ward days, 19 operative procedures, and 85 intensive care unit, high dependency unit, or coronary care unit days. The direct costs of this additional workload approached £160 000. Conclusions: In future discussions on the cost effectiveness of air ambulances, it will be important to consider both the direct and indirect costs to the receiving hospitals arising from the redistribution of emergency workload. Abbreviations: ED, emergency department; HDU, high dependency unit; HEMS, helicopter emergency medical service; ICU, intensive care unit; ISS, injury severity score; WNAA, Warwickshire and Northamptonshire Air Ambulance; WMCAA, West Midlands County Air Ambulance

    Perceived barriers and opportunities to improve working conditions and staff retention in Emergency Departments:a qualitative study

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    Background:Staff retention in Emergency Medicine (EM) is at crisis level and could be attributed in some part to adverse working conditions. This study aimed to better understand current concerns relating to working conditions and working practices in Emergency Departments (EDs).Methods:A qualitative approach was taken, using focus groups with ED staff (doctors, nurses, advanced care practitioners) of all grades, seniority and professional backgrounds from across the UK. Snowball recruitment was undertaken using social media and Royal College of Emergency Medicine communication channels. Focus groups were conducted online and organised by profession. A semi structured topic guide was used to explore difficulties in the work environment, impact of these difficulties, barriers and priorities for change. Data were analysed using a directive content analysis to identify common themes.Results:Of the 116 clinical staff who completed the eligibility and consent forms, 46 met criteria and consented, of those, 33 participants took part. Participants were predominantly White British (85%), female (73%) and doctors (61%). Four key themes were generated: ‘culture of blame and negativity’, ‘Untenable working environments’, ‘compromised leadership’ and ‘striving for support’. Data pertaining to barriers and opportunities for change were identified as sub-themes. In particular, strong leadership emerged as a key driver of change across all aspects of working practices.Conclusion:This study identified four key themes related to workplace concerns and their associated barriers and opportunities for change. Culture, working environment and need for support echoed current narratives across healthcare settings. Leadership emerged more prominently than in prior studies as both a barrier and opportunity for wellbeing and retention in the EM workplace. Further work is needed to develop leadership skills early on in clinical training, provide protected time and opportunity to refine leadership skills and a clear pathway to address higher levels of management
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