9,519 research outputs found

    Earthquake Early Warning and Beyond: Systems Challenges in Smartphone-based Seismic Network

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    Earthquake Early Warning (EEW) systems can effectively reduce fatalities, injuries, and damages caused by earthquakes. Current EEW systems are mostly based on traditional seismic and geodetic networks, and exist only in a few countries due to the high cost of installing and maintaining such systems. The MyShake system takes a different approach and turns people's smartphones into portable seismic sensors to detect earthquake-like motions. However, to issue EEW messages with high accuracy and low latency in the real world, we need to address a number of challenges related to mobile computing. In this paper, we first summarize our experience building and deploying the MyShake system, then focus on two key challenges for smartphone-based EEW (sensing heterogeneity and user/system dynamics) and some preliminary exploration. We also discuss other challenges and new research directions associated with smartphone-based seismic network.Comment: 6 pages, conference paper, already accepted at hotmobile 201

    Leading change in a clinical practice empowering front line staff to lead change

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    This practice-based study investigates the implications for NHS leadership, leadership development and organisation development of the current government's vision of the future NHS as set out in the NHS Improvement Plan (2004). The study is based on two projects; an in-depth organisation development programme located in a high security mental health hospital and a pilot project on the future role of leadership carried out on behalf of the five Strategic Health Authorities in London. The research paradigm is that of naturalistic inquiry using action research and a single case method involving participant observation. Focus groups and a modified Delphi-consultation are used to elicit views about future leadership roles and competences. The two-project design was developed to address the range of leadership roles to be explored, the interplay between leadership development and organisation development and the need to understand both current realities and future developments. The study concludes that successful realisation of the vision set out in the NHS Improvement Plan will require a re-conceptualisation of the roles and competences of both organisational leaders and leaders working at the interface with service users. The study suggests that organisational leaders will need to become adept at shaping the cultures and practices of organisations and systems of organisations (enabling leadership) whereas leaders working at the interface with service users will need to become adept at case management. The study also suggests that leadership development and organisation development need to be closely integrated if either is to make a worthwhile contribution to the development of the NHS. Finally, the study suggest that success in past or current leadership roles in the NHS is likely to be a poor predictor of future success as the leadership requirements of the future will be significantly different from those which prevail currently or which have prevailed in the recent past

    Wide band propagation measurements and ray tracing simulations at 1890 MHz

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    The role of prostaglandin and antioxidant availability in recovery from forearm ischemia-reperfusion injury in humans

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    This article is made available through the Brunel Open Access Publishing Fund. It is shared under the Creative Commons License Attribution-Noncommercial No Derivative 3.0 (CCBY NCND). Copyright @ Lippincott Williams & Wilkins.Background: Endothelial dysfunction, manifesting as attenuated flow-mediated dilation (FMD), is clinically important. Antioxidants may prevent this dysfunction; however, the acute effects of oral administration in humans are unknown. Low flow-mediated constriction (L-FMC), a further parameter of endothelial health, is largely unstudied and the mechanisms for this response unclear. Methods: Twelve healthy participants (five women and seven men) completed three test conditions: control; antioxidant cocktail (α-lipoic acid, vitamins C and E); and prostaglandin inhibitor ingestion (ibuprofen). Ultrasound measurements of brachial artery responses were assessed throughout 5 min of forearm ischemia and 3 min after. Subsequently, an ischemia–reperfusion injury was induced by a 20-min upper arm occlusion. Further, vascular function protocols were completed at 15, 30, and 45 min of recovery. Results: Endothelial dysfunction was evident in all conditions. FMD was attenuated at 15 min after ischemia–reperfusion injury (Pre: 6.24 ± 0.58%; Post15: 0.24 ± 0.75%; mean ± SD, P  0.05). The magnitude of L-FMC was augmented at 15 min (Pre: 1.44 ± 0.27%; Post15: 3.75 ± 1.73%; P < 0.05) and recovered by 45 min. Ibuprofen administration produced the largest constrictive response (Pre: −1.13 ± 1.71%; Post15: −5.57 ± 3.82%; time × condition interaction: P < 0.05). Conclusion: Results demonstrate ischemia–reperfusion injury causes endothelial dysfunction and acute oral antioxidant supplementation fails to reduce its magnitude. Our results also suggest that a lack of shear stress during occlusion combined with suppression of prostaglandin synthesis magnifies L-FMC, possibly due to augmented endothelin-1 expression.Society of Biolog

    Case study based approach to integration of sustainable design analysis, performance and building information modelling

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    This paper presents a case study based research of both the method and technology for integration of sustainable design analysis (SDA) and building information modelling (BIM) within smart built environments (SBE). Level 3 BIM federation and integration challenges are recognised and improvements suggested, including issues with combining geometry and managing attribute data. The research defines SDA as rapid and quantifiable analysis of diverse sustainable alternatives and ‘what if’ scenarios posed by a design team and client during the early stages of the project, where the benefits of correct decisions can significantly exceed the actual investment required. The SDA concept and BIM integration findings are explained through a convergence from conceptualisation to calculation stages, emphasising the importance of an iterative over a linear approach. The approach allowed for a multitude of “what if” scenarios to be analysed, leading to more informed sustainable solutions at the right stages of the project development, with a generally lower level of detail (LOD) and computational/modelling effort required. In addition, the final stage of Building Regulations Part L compliance calculations was reached with a lot greater level of certainty, in terms of its requirements. Finally, a strategy for long term performance monitoring and evaluation of the building design in terms of its environmental sustainability is presented, via integration between BIM and SBE (Smart Built Environment) technologies

    Teaching in the Middle Grades Today: Examining Teachers’ Beliefs About Middle Grades Teaching

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    Since the beginning of the middle school movement in the mid-1960s, middle level advocates have called for a school experience for young adolescents grounded in adolescent development that engages students in meaningful learning (Eichhorn, 1966; Alexander & Williams, 1965). The aim of this exploratory multi-case study was to understand middle level teachers’ beliefs about middle level instruction in the current educational environment. To gain this understanding, researchers asked ten current middle grades teachers with varying levels of experience to discuss their beliefs regarding their primary purpose as a middle grades teacher, the current status of middle level teaching, their best and worst instructional lessons, and their perceived barriers to teaching at the middle level. The teachers described the role of teaching in the middle grades as challenging and stressful, but of great importance. In general, they described instruction that included discovery, student engagement, and relevance in an effort to address students’ academic development. There was minimal mention of the non-academic aspects of adolescent development. Finally, teachers viewed curriculum restrictions, students’ attitudes toward learning, difficulty with differentiation, and lack of technology as significant barriers to their success in the classroom

    Radio pulsars around intermediate mass black holes in super stellar clusters

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    We study accretion in binaries hosting an intermediate mass black hole (IMBH) of 1000 solar masses, and a donor star more massive than 15 solar masses. These systems experience an active X-ray phase characterized by luminosities varying over a wide interval, from <10^36 erg/s up to a few 10^40 erg/s typical of the ultra luminous X-ray sources (ULXs). Roche lobe overflow on the zero-age main sequence and donor masses above 20 solar masses can maintain a long-lived accretion phase at the level required to feed a ULX source. In wide systems, wind transfer rates are magnified by the focusing action of the IMBH yielding wind luminosities around 10^38 erg/s. These high mass-IMBH binaries can be identified as progenitors of IMBH-radio pulsar (PSR) binaries. We find that the formation of an IMBH-PSR binary does not necessarely require the transit through a ULX phase, but that a ULX can highlight a system that will evolve into an IMBH-PSR, if the mass of the donor star is constrained to lie within 15 to 30 solar masses. We show that binary evolution delivers the pre-exploding helium core in an orbit such that after explosion, the neutron star has a very high probability to remain bound to the IMBH, at distances of 1-10 AU. The detection of an IMBH-PSR binary in the Milky Way has suffered, so far, from the same small number of statistics limit affecting the population of ULXs in our Galaxy. Ongoing deeper surveys or next generation radio telescopes like SKA will have an improved chance to unveil such intriguing systems. Timing analysis of a pulsar orbiting around an IMBH would weigh the black hole in the still uncharted interval of mass around 1000 solar massesComment: 10 pages, 8 figures, accepted for publication in MNRAS. Few comments added (minor revision

    Knowing William Faulkner

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    Towards a historical ecology of intertidal foraging in the Mafia Archipelago: archaeomalacology and implications for marine resource management

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    Understanding the timing and nature of human influence on coastal and island ecosystems is becoming a central concern in archaeological research, particularly when investigated within a historical ecology framework. Unfortunately, the coast and islands of eastern Africa have not figured significantly within this growing body of literature, but are important given their historically contingent environmental, social, and political contexts, as well as the considerable threats now posed to marine ecosystems. Here, we begin developing a longer-term understanding of past marine resource use in the Mafia Archipelago (eastern Africa), an area of high ecological importance containing the Mafia Island Marine Park. Focusing on the comparatively less researched marine invertebrates provides a means for initiating discussion on potential past marine ecosystem structure, human foraging and environmental shifts, and the implications for contemporary marine resource management. The available evidence suggests that human-environment interactions over the last 2000 years were complex and dynamic; however, these data raise more questions than answers regarding the specific drivers of changes observed in the archaeomalacological record. This is encouraging as a baseline investigation and emphasizes the need for further engagement with historical ecology by a range of cognate disciplines to enhance our understanding of these complex issues
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