2,720 research outputs found

    Generalised Space-time and Gauge Transformations

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    We consider the generalised space-time introduced by the author in 2003 in the context of the non-linear realisation of the semi-direct product of E11 and its first fundamental representation. For all the fields we propose gauge transformations which are compatible with the underlying E11 structure. A crucial role is played by the generalised vielbein that the generalised space-time possess. We work out the explicit form of the gauge transformations, at low levels, in four, five and eleven dimensions.Comment: 33 page

    Generalised geometry, eleven dimensions and E11

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    We construct the non-linear realisation of E11 and its first fundamental representation in eleven dimensions at low levels. The fields depend on the usual coordinates of space-time as well as two form and five form coordinates. We derive the terms in the dynamics that contain the three form and six form fields and show that when we restricted their field dependence to be only on the usual space-time we recover the correct self-duality relation. Should this result generalise to the gravity fields then the non-linear realisation is an extension of the maximal supergravity theory, as previously conjectured. We also comment on the connections between the different approaches to generalised geometry.Comment: 17 pages, Trivial typos corrected in version one and a substantial note added which gives the equation of motion relating the gravity field to its dua

    E11, generalised space-time and equations of motion in four dimensions

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    We construct the non-linear realisation of the semi-direct product of E11 and its first fundamental representation at low levels in four dimensions. We include the fields for gravity, the scalars and the gauge fields as well as the duals of these fields. The generalised space-time, upon which the fields depend, consists of the usual coordinates of four dimensional space-time and Lorentz scalar coordinates which belong to the 56-dimensional representation of E7. We demand that the equations of motion are first order in derivatives of the generalised space-time and then show that they are essentially uniquely determined by the properties of the E11 Kac-Moody algebra and its first fundamental representation. The two lowest equations correctly describe the equations of motion of the scalars and the gauge fields once one takes the fields to depend only on the usual four dimensional space-time

    Immune activation by combination human lymphokine-activated killer and dendritic cell therapy.

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    BACKGROUND: Optimal cellular immunotherapy for cancer should ideally harness both the innate and adaptive arms of the immune response. Lymphokine-activated killer cells (LAKs) can trigger early innate killing of tumour targets, whereas long-term adaptive-specific tumour control requires priming of CD8+ cytotoxic lymphocytes (CTLs) following acquisition of tumour-associated antigens (TAAs) by antigen-presenting cells such as dendritic cells (DCs). As DCs stimulate both innate and adaptive effectors, combination cell therapy using LAKs and DCs has the potential to maximise anti-tumour immune priming. METHODS: Reciprocal activation between human clinical grade LAKs and DCs on co-culture, and its immune consequences, was monitored by cell phenotype, cytokine release and priming of both innate and adaptive cytotoxicity against melanoma targets. RESULTS: Co-culture of DCs and LAKs led to phenotypic activation of natural killer (NK) cells within the LAK population, which was associated with increased production of inflammatory cytokines and enhanced innate cytotoxicity against tumour cell targets. The LAKs reciprocally matured DCs, and the combination of LAKs and DCs, on addition of melanoma cells, supported priming of specific anti-tumour CTLs better than DCs alone. CONCLUSION: Clinical-grade LAKs/DCs represents a practical, effective combination cell immunotherapy for stimulation of both innate and adaptive anti-tumour immunity in cancer patients

    3D printed ultrasound phantoms for clinical training

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    Ultrasound is a ubiquitous, portable structural imaging technique which is used to provide visual feedback for a range of diagnostic and surgical techniques. Training for these techniques demands a range of teaching models tailored for each application. Existing anatomical models are often overly simple or prohibitively expensive, causing difficulties in obtaining patient or procedure specific models. In this study we present ultrasonic rib phantoms for clinical teaching and training purposes, fabricated by three-dimensional (3D) printing technologies. Models were produced using freely available software and data, and their effectiveness as teaching phantoms evaluated using clinical ultrasound scans of the phantoms

    Duality Invariant Actions and Generalised Geometry

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    We construct the non-linear realisation of the semi-direct product of E(11) and its first fundamental representation at lowest order and appropriate to spacetime dimensions four to seven. This leads to a non-linear realisation of the duality groups and introduces fields that depend on a generalised space which possess a generalised vielbein. We focus on the part of the generalised space on which the duality groups alone act and construct an invariant action.Comment: 59 pages (typos fixed and added comments

    Rationalizations and identity conflict following smoking relapse: a thematic analysis

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    Introduction: Little is known about how smokers respond cognitively and emotionally to the experience of “late” relapse after the acute withdrawal phase. This study assessed the kinds of thoughts and feelings that emerge in order to provide a basis for quantitative research assessing prevalence of different types of response and implications for future quit attempts. Methods: Face-to-face in-depth interviews were conducted among 14 people attending a quit smoking clinic in Malaysia who had relapsed after at least 6 weeks of abstinence. Transcripts were analyzed using thematic analysis to enable emergence of important aspects of the experience. Results: Following relapse, smokers often engaged in rationalizations and activities to minimize worry about the harmful effects of smoking by switching to a lower-tar cigarette, reducing the number of cigarette smoked, attempting to reduce cigarette smoke inhalation, comparing themselves with other smokers, and minimizing the health risks associated with smoking. In some cases, smokers retained a “non-smoker” identity despite having relapsed. Conclusion: Smoking relapsers rationalize their failure to quit and minimize their health risk in order to protect their image as non-smokers while it remains a source of identity conflict

    Generalized Geometry and M theory

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    We reformulate the Hamiltonian form of bosonic eleven dimensional supergravity in terms of an object that unifies the three-form and the metric. For the case of four spatial dimensions, the duality group is manifest and the metric and C-field are on an equal footing even though no dimensional reduction is required for our results to hold. One may also describe our results using the generalized geometry that emerges from membrane duality. The relationship between the twisted Courant algebra and the gauge symmetries of eleven dimensional supergravity are described in detail.Comment: 29 pages of Latex, v2 References added, typos fixed, v3 corrected kinetic term and references adde

    Occupational balance: What tips the scales for new students?

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    The open question, ‘What prevents you from reaching occupational balance?’, was posed within a questionnaire aimed at exploring the meanings of occupation, health and wellbeing with a cohort of first-year occupational therapy students during their initial few weeks at university. Their written responses to the question about occupational balance were analysed and are discussed in this paper. Not surprisingly, occupational balance appeared to be achieved by only a few and more by chance than design. People, time and money factors were identified as the main impediments to achieving occupational balance, with psychological and emotional pressures being at the forefront. Interestingly, despite these barriers, the overall educational benefit of considering the occupational balance question in this way raised the students’ awareness of its relationship to health and wellbeing. This increased awareness might have longer-term health benefits, both personally and professionally, which would be worthy of further research

    Lessons learned from unsuccessful use of personal carbon monoxide monitors to remotely assess abstinence in a pragmatic trial of a smartphone stop smoking app – a secondary analysis

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    INTRODUCTION: Verifying abstinence remotely in trials of digital cessation interventions remains a major challenge. This study reports on using personal carbon monoxide (CO) monitors to assess abstinence in a pragmatic trial of a standalone cessation app involving automated recruitment with no researcher contact. METHODS: The study involved secondary data analysis of remote CO testing in a randomized trial (ISRCTN10548241) comparing two versions of a cessation app (BupaQuit). Trial participants were adult UK-based smokers interested in quitting, who were recruited online (02/2015–03/2016). Participants were followed-up through the app, email or phone at 4 weeks. Fifty-nine participants reporting not smoking were posted a personal CO monitor with instructions, and emailed two reminders. The monitors required installing software on a Windows PC. Participants were not reimbursed but retained the device. We recorded the proportion of CO tests returned, test results, self-reported ease of use, correct use, acceptability, and reasons for missing results. RESULTS: Fifteen (25.4%) CO results were returned, of which 86.6% were <10 ppm and 53.3% were <5 ppm, indicating abstinence (corresponding to 20.9% and 12.9% of all trial participants self-reporting abstinence, respectively). These 15 participants found the test easy, acceptable and believed they conducted it correctly. Eight (18.2%) of the missing results were accounted for, including no access to a Windows PC, barriers to receiving packages, and unwillingness to share results. CONCLUSION: Remote validation using personal CO monitors may not yet be feasible in pragmatic studies of cessation apps in which participants are recruited with no reimbursement or direct contact with researchers
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