Penrose Diagram for a Transient Black Hole

A Penrose diagram is constructed for a spatially coherent black hole that smoothly begins an accretion, then excretes symmetrically as measured by a distant observer, with the initial and final states described by a metric of Minkowski form. Coordinate curves on the diagram are computationally derived. Causal relationships between space-time regions are briefly discussed. The life cycle of the black hole demonstrably leaves asymptotic observers in an unaltered Minkowski space-time of uniform conformal scale.Comment: 14 pages, 9 figures, spelling correction

Black Hole - Never Forms, or Never Evaporates

Many discussion about the black hole conundrums, such as singularity and information loss, suggested that there must be some essential irreconcilable conflict between quantum theory and classical gravity theory, which cannot be solved with any semiclassical quantized model of gravity, the only feasible way must be some complete unified quantum theory of gravity. In \cite{Vachaspati2007a}, the arguments indicate the possibility of an alternate outcome of gravitational collapse which avoids the information loss problem. In this paper, also with semiclassical analysis, it shows that so long as the mechanism of black hole evaporation satisfies a quite loose condition that the evaporation lifespan is finite for external observers, regardless of the detailed mechanism and process of evaporation, the conundrums above can be naturally avoided. This condition can be satisfied with Hawking-Unruh mechanism. Thus, the conflict between quantum theory and classical gravity theory may be not as serious as it seemed to be, the effectiveness of semiclassical methods might be underestimated. An exact universal solution with spherical symmetry of Einstein field equation has been derived in this paper. All possible solutions with spherical symmetry of Einstein field equation are its special cases. In addition, some problems of the Penrose diagram of an evaporating black hole first introduced by Hawking in 1975 \cite{Hawking1975} are clarified.Comment: 17 pages, 7 figures. Compared to the published version in JCAP, some minimal typeset error has been correcte

Avoidance of wind farms by harbour seals is limited to pile driving activities

DJFR, GH, VMJ and BM were funded by the UK Department of Energy and Climate Change (DECC) as part of their Offshore Energy Strategic Environmental Assessment programme. DT and GH were also funded by NERC/Defra EBAO NE/J004243/1. ELJ was funded under Scottish Government grant MMSS001/01. This work was also supported by National Capability funding from the Natural Environment Research Council to SMRU (grant no. SMRU1001). Tags and their deployment in the Thames in 2006 and The Wash were funded by DECC. Tags and their deployment in the Thames in 2012 were commissioned by Zoological Society London, with funding from BBC Wildlife Fund and Sita Trust.1. As part of global efforts to reduce dependence on carbon-based energy sources there has been a rapid increase in the installation of renewable energy devices. The installation and operation of these devices can result in conflicts with wildlife. In the marine environment, mammals may avoid wind farms that are under construction or operating. Such avoidance may lead to more time spent travelling or displacement from key habitats. A paucity of data on at-sea movements of marine mammals around wind farms limits our understanding of the nature of their potential impacts. 2. Here, we present the results of a telemetry study on harbour seals Phoca vitulina in The Wash, south-east England, an area where wind farms are being constructed using impact pile driving. We investigated whether seals avoid wind farms during operation, construction in its entirety, or during piling activity. The study was carried out using historical telemetry data collected prior to any wind farm development and telemetry data collected in 2012 during the construction of one wind farm and the operation of another. 3. Within an operational wind farm, there was a close-to-significant increase in seal usage compared to prior to wind farm development. However, the wind farm was at the edge of a large area of increased usage, so the presence of the wind farm was unlikely to be the cause. 4. There was no significant displacement during construction as a whole. However, during piling, seal usage (abundance) was significantly reduced up to 25 km from the piling activity; within 25 km of the centre of the wind farm, there was a 19 to 83% (95% confidence intervals) decrease in usage compared to during breaks in piling, equating to a mean estimated displacement of 440 individuals. This amounts to significant displacement starting from predicted received levels of between 166 and 178 dB re 1 μPa(p·p). Displacement was limited to piling activity; within 2 h of cessation of pile driving, seals were distributed as per the non-piling scenario. 5. Synthesis and applications. Our spatial and temporal quantification of avoidance of wind farms by harbour seals is critical to reduce uncertainty and increase robustness in environmental impact assessments of future developments. Specifically, the results will allow policymakers to produce industry guidance on the likelihood of displacement of seals in response to pile driving; the relationship between sound levels and avoidance rates; and the duration of any avoidance, thus allowing far more accurate environmental assessments to be carried out during the consenting process. Further, our results can be used to inform mitigation strategies in terms of both the sound levels likely to cause displacement and what temporal patterns of piling would minimize the magnitude of the energetic impacts of displacement.Publisher PDFPeer reviewe

Virtual discussions to support climate risk decision making on farms

Climate variability represents a significant risk to farming enterprises. Effective extension of climate information may improve climate risk decision making and adaptive management responses to climate variability on farms. This paper briefly reviews current agricultural extension approaches and reports stakeholder responses to new web-based virtual world ‘discussion-support’ tools developed for the Australian sugar cane farming industry. These tools incorporate current climate science and sugar industry better management practices, while leveraging the social-learning aspects of farming, to provide a stimulus for discussion and climate risk decision making. Responses suggest that such virtual world tools may provide effective support for climate risk decision making on Australian sugar cane farms. Increasing capacity to deliver such tools online also suggests potential to engage large numbers of farmers globally

Leadership in Community Nursing - Report of a study carried out by Queen Margaret University Edinburgh, NHS Lanarkshire and NHS Forth Valley

Study funded by Queens Nursing Institute ScotlandIn response to national and local agendas, both NHS Lanarkshire and NHS Forth Valley maintain a strong commitment to the development of those in clinical leadership positions. Queen Margaret University programmes in Nursing incorporate leadership as a core element in preparation for practice, and QMU have accredited NHS Lanarkshire's leadership educational programme for several years. This project emerged from that collaboration, from ideas about the nature of leadership and the recognition that few empirical studies exist in nursing in general, and fewer specifically in community nursing. The two data collection sites were not involved in pilot work of the Review of Nursing in the Community (SEHD 2006) although all staff were working in this context of policy drivers encouraging change (SE 2005a, SE 2005b, Pollock 2007, Kennedy et al 2009, RCN 2009a 2009b).sch_nurAntrobus S, Kitson A (1999) Nursing leadership: influencing and shaping health policy and nursing practice. Journal of Advanced Nursing 29 (3) 746 - 753 Boumans, N.P. & Landeweerd, J.A. (1993) Leadership in the Nursing Unit: Relationships with Nurses' Well-being. Journal of Advanced Nursing 18 pp.767-775. Bowles A, Bowles N B (2000) A comparative study of transformational leadership in nursing development units and conventional clinical settings. Journal of Nursing Management 8 69 - 76 Cain M (2005) Essential qualities of an effective clinical leader. Dimensions of Critical Care Nursing 24 (1) 32-4 Cook M J, Leathard H L (2004) Learning for clinical leadership. Journal of Nursing Management 12 436 - 444 Kennedy C., Christie J., Harbison J., Maxton F., Rutherford I. & Moss D. (2008), Establishing the contribution of nursing in the community to the health of the people of Scotland: integrative literature review. Journal of Advanced Nursing 64(5), 416-439 Kennedy C, Elliott L, Rush R, Hogg R, Cameron S, Currie M, Hall S, Miller M, Plunkett, S Lauder W (2009) Review of Community Nursing: baseline study. Available at: http://www.scotland.gov.uk/socialresearch McKenna H, Keeney S, Bradley M (2004) Nurse leadership within primary care: the perceptions of community nurse, GPs, policy makers and members of the public. Journal of Nursing Management 12 69 - 76 Morton J (1999) A model of leadership for community nurses. Journal of Community Nursing 13 (5) 8 - 11 Pollock L (2007) Responses to Visible, Accessible and Integrated Care - the Practitioners' Voice.- Edinburgh: QNIS. Ritchie, J and Spencer, L (1994), 'Qualitative data analysis for applied policy research', in Bryman and Burgess, eds., Analysing Qualitative Data, London: Routledge, p173-194. Royal College of Nursing (2009a) A Sustainable Future: the RCN Vision for Community Nursing in Scotland http://www.rcn.org.uk/__data/assets/pdf_file/0006/238092/RCN_vision_for_Community_Nursing_in_Scotland.pdf Royal College of Nursing (2009b) A Sustainable Future: Voices on a Vision http://www.rcn.org.uk/__data/assets/pdf_file/0015/238101/A_Sustainable_Future_Voices_on_a_Vision.pdf Scottish Executive (2005a) Building a health service fit for the future: a national framework for service change in the NHS in Scotland (The Kerr Report-) Edinburgh, Scottish Executive http://www.scotland.gov.uk/Resource/Doc/924/0012112.pdf Scottish Executive (2005b) Delivering for Health Edinburgh, Scottish Executive http://www.scotland.gov.uk/Publications/2005/11/02102635/26356 Scottish Executive Health Department (SEHD) (2006) Visible, accessible and integrated care. Report of the review of nursing in the community in Scotland. Edinburgh: HMSO Smith, M. A. (2004). Health visiting: the public health role. Journal of Advanced Nursing, 45 (1), pp.17-25. Stanley D (2006) Recognising and defining clinical nurse leaders. British Journal of Nursing 15 (2) 108 - 111 Thurtle, V., Saunders, M. and Clarridge, A. (2006). Advancing practice by developing a primary care nursing programme. British Journal of Community Nursing, 11 (4), pp.167-173. Tweddell L (2007) Health visiting faces fundamental change to cope with future need. Nursing Times 103 (26) 9 Wong CA, Cummings G G (2007) Relationship between nurse leadership and patient outcomes - a systematic review. Journal of Nursing Management. 15 (5) 508 - 521pub4561pu

Tunnelling Methods and Hawking's radiation: achievements and prospects

The aim of this work is to review the tunnelling method as an alternative description of the quantum radiation from black holes and cosmological horizons. The method is first formulated and discussed for the case of stationary black holes, then a foundation is provided in terms of analytic continuation throughout complex space-time. The two principal implementations of the tunnelling approach, which are the null geodesic method and the Hamilton-Jacobi method, are shown to be equivalent in the stationary case. The Hamilton-Jacobi method is then extended to cover spherically symmetric dynamical black holes, cosmological horizons and naked singularities. Prospects and achievements are discussed in the conclusions.Comment: Topical Review commissioned and accepted for publication by "Classical and Quantum Gravity". 101 pages; 6 figure

Vocal foragers and silent crowds : context-dependent vocal variation in Northeast Atlantic long-finned pilot whales

This study was financially supported by the US Office of Naval Research, The Netherlands Ministry of Defence, the Norwegian Research Council and the Norwegian Ministry of Defence.Vocalisations form a key component of the social interactions and foraging behaviour of toothed whales. We investigated changes in calling and echolocation behaviour of long-finned pilot whales between foraging and non-foraging periods, by combining acoustic recordings and diving depth data from tagged individuals with concurrent surface observations on social behaviour of their group. The pilot whales showed marked vocal variation, specific to foraging and social context. During periods of foraging, pilot whales showed more vocal activity than during non-foraging periods (rest, travel). In addition to the expected increase in echolocation activity, call rates also increased, suggesting that pilot whales communicate more during foraging. Furthermore, calls with multiple inflections occurred more often immediately before and after foraging dives and during the early descent and late ascent phases of foraging dives. However, these calls were almost never detected at diving depths of the tagged whale beyond 350 m. Calls with no or few inflections were produced at all times, irrespective of diving depth of the tagged whale. We discuss possible explanations for the distinct vocal variation associated with foraging periods. In addition, during non-foraging periods, the pilot whales were found to be more silent (no calling or echolocation) in larger, more closely spaced groups. This indicates that increased levels of social cohesion may release the need to stay in touch acoustically. Significance statement: Social toothed whales rely on vocalisations to find prey and interact with conspecifics. Species are often highly vocal and can have elaborate call repertoires. However, it often remains unclear how their repertoire use correlates to specific social and behavioural contexts, which is vital to understand toothed whale foraging strategies and sociality. Combining on-animal tag recordings of diving and acoustic behaviour with observations of social behaviour, we found that pilot whales produce more calls during foraging than during non-foraging periods. Moreover, highly inflected calls were closely associated to the periods around and during foraging dives. This indicates enhanced communication during foraging, which may, for example, enable relocation of conspecifics or sharing of information. Whales reduced their vocal activity (calling and echolocation) at increased levels of social cohesion, indicating that in certain behavioural contexts, closer association (i.e. more closely spaced) may release the need to stay in touch acoustically.Publisher PDFPeer reviewe

An evaluation of primary care led dementia diagnostic services in Bristol

© 2014 Dodd et al. Background: Typically people who go to see their GP with a memory problem will be initially assessed and those patients who seem to be at risk will be referred onto a memory clinic. The demographic forces mean that memory services will need to expand to meet demand. An alternative may be to expand the role of primary care in dementia diagnosis and care. The aim of this study was to contrast patient, family member and professional experience of primary and secondary (usual) care led memory services. Methods: A qualitative, participatory study. A topic guide was developed by the peer and professional panels. Data were collected through peer led interviews of people with dementia, their family members and health professionals. Results: Eleven (21%) of the 53 GP practices in Bristol offered primary care led dementia services. Three professional panels were held and were attended by 9 professionals; nine carers but no patients were involved in the three peer panels. These panels identified four main themes: GPS rarely make independent dementia diagnosis; GPS and memory nurses work together; patients and carers generally experience a high quality diagnostic service; an absence of post diagnostic support. Evidence relating to these themes was collected through a total of 46 participants took part; 23 (50%) in primary care and 23 (50%) in the memory service. Conclusions: Patients and carers were generally satisfied with either primary or secondary care led approaches to dementia diagnosis. Their major concern, shared with many health care professionals, was a lack of post diagnostic support

Virtual Discussions to Support Climate Risk Decision Making on Farms

Climate variability represents a significant risk to farming enterprises. Effective extension of climate information may improve climate risk decision making and adaptive management responses to climate variability on farms. This paper briefly reviews current agricultural extension approaches and reports stakeholder responses to new web-based virtual world ‘discussion-support’ tools developed for the Australian sugar cane farming industry. These tools incorporate current climate science and sugar industry better management practices, while leveraging the social-learning aspects of farming, to provide a stimulus for discussion and climate risk decision making. Responses suggest that such virtual world tools may provide effective support for climate risk decision making on Australian sugar cane farms. Increasing capacity to deliver such tools online also suggests potential to engage large numbers of farmers globally

The Development of Virtual World Tools to Enhance Learning and Real World Decision Making in the Australian Sugar Farming Industry

In farming, the outcome of critical decisions to enhance productivity and profitability and so ensure the viability of farming enterprises is often influenced by seasonal conditions and weather events over the growing season. This paper reports on a project that uses cutting-edge advances in digital technologies and their application in learning environments to develop and evaluate a web-based virtual ‘discussion-support’ system for improved climate risk management in Australian sugar farming systems. Customized scripted video clips (machinima) are created in the Second Life virtual world environment. The videos use contextualized settings and lifelike avatar actors to model conversations about climate risk and key farm operational decisions relevant to the real-world lives and practices of sugarcane farmers. The tools generate new cognitive schema for farmers to access and provide stimuli for discussions around how to incorporate an understanding of climate risk into operational decision-making. They also have potential to provide cost-effective agricultural extension which simulates real world face-to-face extension services but is accessible anytime anywhere