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    Abstract Tensor Systems as Monoidal Categories

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    The primary contribution of this paper is to give a formal, categorical treatment to Penrose's abstract tensor notation, in the context of traced symmetric monoidal categories. To do so, we introduce a typed, sum-free version of an abstract tensor system and demonstrate the construction of its associated category. We then show that the associated category of the free abstract tensor system is in fact the free traced symmetric monoidal category on a monoidal signature. A notable consequence of this result is a simple proof for the soundness and completeness of the diagrammatic language for traced symmetric monoidal categories.Comment: Dedicated to Joachim Lambek on the occasion of his 90th birthda

    A Critical Review of the Magnetoplasmadynamic /MPD/ Thrustor for Space Applications

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    Magnetoplasmadynamic thrustor for space application

    Historical Internal Migration in Ireland

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    Copyright & reuse City University London has developed City Research Online so that its users may access the research outputs of City University London's staff. Copyright © and Moral Rights for this paper are retained by the individual author(s) and / or other copyright holders. All material in City Research Online is checked for eligibility for copyright before being made available in the live archive. URLs from City Research Online may be freely distributed and linked to from other web pages. Versions of research The version in City Research Online may differ from the final published version. Users are advised to check the Permanent City Research Online URL above for the status of the paper. Enquiries If you have any enquiries about any aspect of City Research Online, or if you wish to make contact with the author(s) of this paper, please email the team at [email protected]

    Büchwald-Hartwig reaction applied to synthesis of new luminescent liquid crystal triarylamines derived from isoxazoles

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    © 2015 Taylor & Francis Group, LLC. The present work describes the synthesis and characterization of novel series of triarylamines isoxazoles (TAA) addressed to the organic photovoltaic materials. Diarylisoxazoles were synthesized by sequential [3+2] 1,3-dipolar cycloaddition reaction between arylnitrile oxides and selected arylalkenes followed by MnO2-oxidation. Isoxazoles were coupled to diarylamines by Büchwald-Hartwig reaction to afford desired compounds 6a-k. Some TAA display liquid-crystalline behaviour and UV-Vis absorption and fluorescence emission were analysed for all samples of TAA 6a-k

    Working with school-refusing young people in Tower Hamlets, London

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    This study looks at the local context, describing quantitative data from a subset of young people seen within the inner London Tower Hamlets Pupil Referral Unit (PRU) that are extremely socially withdrawn and unable to attend mainstream education. The core aim of this research was to examine the views of professionals who work with and for these young people. Qualitative group interviews were used to gain a deeper understanding of the needs of these young people, what might contribute to their withdrawal from school and what needs to be done to help them reintegrate. Professionals reported that these young people were highly complex in terms of their needs and presentation and that there is a lack of clarity around what causes these young people to withdraw. They agreed that a more intensive multi-layered intervention was required to meet their needs. Interventions that include gradual socialisation, parental involvement and which address the role of technology were indicated. However, more research is needed to clarify how to effectively intervene

    Electron density and temperature measurements in the exhaust of a mpd source

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    Electron density and temperature profiles measured in exhaust of magnetoplasma-dynamic sourc

    Injury in Ireland

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    Injury mortality is the fourth commonest cause of death in Ireland. The treatment of injuries has a major impact on our hospitals and on our budget for health. Long term disability following accidents is a serious problem. The aim of this report is to examine the impact of accidents and injuries on the Irish population by analysing routine mortality and morbidity data, and to identify in turn those areas where preventive measures could have an impact. In Section One the literature review details the advantages and disadvantages of each type of routine data source used in this report. The interpretation of data should take account of the constraints of the available data collected. The usefulness of routine data collection is highlighted, while identifying areas for improvement. In Section Two the methodology employed in the study is detailed. In Section Three data on hospital admissions over a five-year period 1993-1997 are presented. An overview of injury admissions is presented, followed by further analysis of injury data by both cause and by age group. In Section Four data on all accident-related deaths over a 17-year period, 1980-1996, are presented, with overall mortality data and mortality data by age group and by major causes of injury death detailed. In Section Five comparisons are made between the eight health board regions for rates of admissions and deaths due to injury. In presenting the data we use a matrix format devised and recommended by the International Collaborative Effort on Injury Statistics to display injury simultaneously by cause and intent. The use of a common format will also facilitate regional and international comparisons. In Section Six the priority recommendations for injury prevention are outlined. The key findings are then discussed and further recommendations are presented with the aim of injury prevention, reduction of disability and improvement in injury surveillance
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