118 research outputs found

    The social work team : team practice in the family service departments of the Children\u27s Aid Society of Metropolitan Toronto.

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    Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1975 .M54. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.S.W.)--University of Windsor (Canada), 1975

    An experimental and computational study of two state of the art living free radical polymerisation techniques

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    This thesis describes the research conducted by t he author in completion of a Doctor of Philosophy in the Centre for Advanced Macromolecular Design(CAMD), Univcrsity of New South Wales (UNSW) , Sydney, Australia; under the supervision of Professor Christopher Barner-Kowollik and Doctor Michelle L. Coote (Australian National University). The research has led to the creation of new knowledge in the fields of free radical polymerisation and chemical kinetics. Research was conducted in two main thrusts: (1) investigation into the governing kinetic processes behind star polymer synthesis via what has become known as a reversible addition fragmentation chain transfer (RAFT), R-group approach and (2) an entirely new mode of living free radical (LFR) polymerisation which has been named thioketone mediated polymerisation (TKMP). In the first broad area of the described research, a novel kinetic modelling scheme has been developed in which only the reactions of a single arm star are simulated explicitly. Subsequently, the molecular weight distributions (MWDs) arising from the single arm star simulation are convolved, using probabilistic calculations, to generate the MWD appropriate to a multi-arm star polymerisat ion bearing t he same kinetic parameters as the single arm one. This model is validated against experimental data, enabling, for the first time, the use of rigorous theoretical reasoning to distill a set of synthetic guidelines for star polymer synthesis via a RAFT, R-group approach. Subsequently, the product spectra resulting from RAFT, R-group approach polymerisations of para-acetoxystyrene have been analysed via mass spectrometry. This has led to direct evidence for many of the complex species whose existence had, up until this point, been inferred from gel permeation chromatography (GPC) measured MWDs. The menagerie of species identified includes, but is not limited to, star-star couples, initiator fragment terminated stars, initiator fragment terminated star-star couples and linear chains -- both living and terminated. Using a kinetic model devised specifically for application in mass spectrometry analysis, the experimentally observed abundances of each of the above species have been compared to t hose predicted by simulation. The qualitative agreement between the predicted and observed abundances has provided additional evidence that t he proposed mechanism for RAFT, R-group approach polymerisations is correct and operative. Further, it seems unlikely that significant, undiscovered kinetic phenomena exist. Due to (a) long simulation times encountered using the state of the art, commercial partial differential equation solver for polymerisation kinetics (i.e. PREDICI, Computing in Technology (CiT), GmbH; see http://www.cit-wulkow.de) and (b) the limited flexibility this software provides with respect to the types of chemical species that can be simulated, fundamental research has been conducted into the kinetic Monte Carlo method to (i) examine fundamental aspects of this simulation approach; (ii) determine the maximum speed attainable through a combination of optimisations including run-time generation of problem specific code and parallelisation; and, therefore (iii) find out what the potential of this method may be as a replacement for t he existing methods. In terms of speed, the developed code outperforms previous Monte Carlo benchmarks in the literature by a factor of 2.6 and the latest developments in the commercial tool, PREDICI that took place during the author's Ph.D. candidature give it similar performance to the herein described Monte Carlo code; however, the latter is required to run on multiple processors in order to compete with the serial algorithm implemented in PREDICI. The Monte Carlo method does, however, provide complete freedom with respect to the chemical species whose kinetics can be simulated, allowing for complex species with many chain lengths and, in principal copolymer compositions and branched structures. The Monte Carlo approach is the method of choice for these types of simulations and for the first time competes with the commercial tool in terms of speed. In the second broad area of the described research, an experimental investigation has been conducted into the applicability of thioketones, S=C (R1) (R2), as mediating agents for free radical polymerisations. The compound di-tert-butyl thioketone (DTBT), S=C-(C(CH3)3)2, has been chosen as a model reagent and this, when incorporated into a free radical polymerisation of styrene has led to a linear increase of the average molecular weight as conversion of monomer into polymer takes place - demonstrating control. A reversible radical trapping mechanism has been proposed and evidence for this has been provided in the form of an ab initio calculation of the equilibrium constant for the trapping of a styryl dimer radical by DTBT. This equilibrium constant was approximately K = 105 L mol-1 and is close to the value which is expected on the basis of the experimental results. To aid future experimental investigations intoTKMP, a quantum chemical survey has, been conducted with the aim of discovering the radical affinities of a large range of thioketones. It has been demonstrated that there is ample scope within this class of compound for potent radical trapping - far above that of DTBT. The affinities of various thioketone substrates for radicals have been understood in terms of the radical stabilising and thioketone destabilising effect of the two substituents R1 and R2 on, respectively, the adduct radical, R-S-C•(R1) (R2), and the parent thioketone. All results appearing in this thesis have been published previously in peer-reviewed scientific journals

    Perspectives on the policy ‘black box’: a comparative case study of orthopaedics services in England

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    AbstractThere has been much recent debate on the impact of competition on the English National Health Service (NHS). However, studies have tended to view competition in isolation and are controversial. This study examines the impact of programme theories associated with the health system reforms, which sought to move from a dominant target-led ‘central control’ programme theory, to one based on ‘market forces’, on orthopaedics across six case-study local health economies. It draws on a realistic evaluation approach to open up the policy ‘black box’ across different contexts using a mixed methods approach: analysis of 152 interviews with key informants and analysis of waiting times and admissions. We find that the urban health economies were more successful in reaching the access targets than the rural health economies, although the gap in performance closed over time. Most interviewees were aware of the policies to increase choice and competition, but their role appeared comparatively weak. Local commissioners’ ability to influence demand appeared limited with providers’ incentives dominating service delivery. Looking forward, it is clear that the role of competition in the NHS has to be considered alongside, rather than in isolation from, other policy mechanisms.</jats:p

    Towards achieving interorganisational collaboration between health-care providers:a realist evidence synthesis

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    Background Interorganisational collaboration is currently being promoted to improve the performance of NHS providers. However, up to now, there has, to the best of our knowledge, been no systematic attempt to assess the effect of different approaches to collaboration or to understand the mechanisms through which interorganisational collaborations can work in particular contexts. Objectives Our objectives were to (1) explore the main strands of the literature about interorganisational collaboration and to identify the main theoretical and conceptual frameworks, (2) assess the empirical evidence with regard to how different interorganisational collaborations may (or may not) lead to improved performance and outcomes, (3) understand and learn from NHS evidence users and other stakeholders about how and where interorganisational collaborations can best be used to support turnaround processes, (4) develop a typology of interorganisational collaboration that considers different types and scales of collaboration appropriate to NHS provider contexts and (5) generate evidence-informed practical guidance for NHS providers, policy-makers and others with responsibility for implementing and assessing interorganisational collaboration arrangements. Design A realist synthesis was carried out to develop, test and refine theories about how interorganisational collaborations work, for whom and in what circumstances. Data sources Data sources were gathered from peer-reviewed and grey literature, realist interviews with 34 stakeholders and a focus group with patient and public representatives. Review methods Initial theories and ideas were gathered from scoping reviews that were gleaned and refined through a realist review of the literature. A range of stakeholder interviews and a focus group sought to further refine understandings of what works, for whom and in what circumstances with regard to high-performing interorganisational collaborations. Results A realist review and synthesis identified key mechanisms, such as trust, faith, confidence and risk tolerance, within the functioning of effective interorganisational collaborations. A stakeholder analysis refined this understanding and, in addition, developed a new programme theory of collaborative performance, with mechanisms related to cultural efficacy, organisational efficiency and technological effectiveness. A series of translatable tools, including a diagnostic survey and a collaboration maturity index, were also developed. Limitations The breadth of interorganisational collaboration arrangements included made it difficult to make specific recommendations for individual interorganisational collaboration types. The stakeholder analysis focused exclusively on England, UK, where the COVID-19 pandemic posed challenges for fieldwork. Conclusions Implementing successful interorganisational collaborations is a difficult, complex task that requires significant time, resource and energy to achieve the collaborative functioning that generates performance improvements. A delicate balance of building trust, instilling faith and maintaining confidence is required for high-performing interorganisational collaborations to flourish. Future work Future research should further refine our theory by incorporating other workforce and user perspectives. Research into digital platforms for interorganisational collaborations and outcome measurement are advocated, along with place-based and cross-sectoral partnerships, as well as regulatory models for overseeing interorganisational collaborations. Study registration The study is registered as PROSPERO CRD42019149009. Funding This project was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme and will be published in full in Health and Social Care Delivery Research; Vol. 11, No. 6. See the NIHR Journals Library website for further project information

    How, when, and why do inter-organisational collaborations in healthcare work? A realist evaluation

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    BackgroundInter-organisational collaborations (IOCs) in healthcare have been viewed as an effective approach to performance improvement. However, there remain gaps in our understanding of&nbsp;what&nbsp;helps IOCs function, as well as&nbsp;how&nbsp;and&nbsp;why&nbsp;contextual elements affect their implementation. A realist review of evidence drawing on 86 sources has sought to elicit and refine context-mechanism-outcome configurations (CMOCs) to understand and refine these phenomena, yet further understanding can be gained from interviewing those involved in developing IOCs.MethodsWe used a realist evaluation methodology, adopting prior realist synthesis findings as a theoretical framework that we sought to refine. We drew on 32 interviews taking place between January 2020 and May 2021 with 29 stakeholders comprising IOC case studies, service users, as well as regulatory perspectives in England. Using a retroductive analysis approach, we aimed to test CMOCs against these data to explore whether previously identified mechanisms, CMOCs, and causal links between them were affirmed, refuted, or revised, and refine our explanations of how and why interorganisational collaborations are successful.ResultsMost of our prior CMOCs and their underlying mechanisms were supported in the interview findings with a diverse range of evidence. Leadership behaviours, including showing vulnerability and persuasiveness, acted to shape the core mechanisms of collaborative functioning. These included our prior mechanisms of trust, faith, and confidence, which were largely ratified with minor refinements. Action statements were formulated, translating theoretical findings into practical guidance.ConclusionAs the fifth stage in a larger project, our refined theory provides a comprehensive understanding of the causal chain leading to effective collaborative inter-organisational relationships. These findings and recommendations can support implementation of IOCs in the UK and elsewhere. Future research should translate these findings into further practical guidance for implementers, researchers, and policymakers.</p

    Does sticky blood predict a sticky end? Associations of blood viscosity, haematocrit and fibrinogen with mortality in the West of Scotland

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    There is increasing evidence that blood viscosity and its major determinants (haematocrit, plasma viscosity and fibrinogen) are associated with an increased risk of incident cardiovascular events; however, their associations with mortality are not established. We therefore studied the associations of these variables with cardiovascular events and total mortality in 1238 men and women aged 25-64 years, followed for 13 years in the first North Glasgow MONICA (MONItoring CArdiovascular disease) survey and West of Scotland centres in the Scottish Heart Health Study. After adjustment for age and sex, increasing whole blood viscosity, plasma viscosity, haematocrit and fibrinogen (analysed by both von Clauss and heat precipitation assays) were significantly associated with mortality. Only the association for fibrinogen (von Clauss assay) remained significant after adjustment for major cardiovascular risk factors. We conclude that clottable fibrinogen may be independently associated with mortality. However, the significance of this association, and the extent to which viscosity is associated with mortality, remain to be established in larger studies and meta-analyses

    Organ specificity in the plant circadian system is explained by different light inputs to the shoot and root clocks

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    Circadian clocks allow the temporal compartmentalisation of biological processes. In Arabidopsis circadian rhythms display organ specificity but the underlying molecular causes have not been identified. We investigated the mechanisms responsible for the similarities and differences between the clocks of mature shoots and roots in constant conditions and in light:dark cycles. We developed an imaging system to monitor clock gene expression in shoots and light- or dark-grown roots, modified a recent mathematical model of the Arabidopsis clock and used this to simulate our new data. We showed that the shoot and root circadian clocks have different rhythmic properties (period and amplitude) and respond differently to light quality. The root clock was entrained by direct exposure to low-intensity light, even in antiphase to the illumination of shoots. Differences between the clocks were more pronounced in conditions where light is present than in constant darkness, and persisted in the presence of sucrose. We simulated the data successfully by modifying those parameters of a clock model that are related to light inputs. We conclude that differences and similarities between the shoot and root clocks can largely be explained by organ-specific light inputs. This provides mechanistic insight into the developing field of organ-specific clocks

    The Global Trachoma Mapping Project: Methodology of a 34-Country Population-Based Study.

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    PURPOSE: To complete the baseline trachoma map worldwide by conducting population-based surveys in an estimated 1238 suspected endemic districts of 34 countries. METHODS: A series of national and sub-national projects owned, managed and staffed by ministries of health, conduct house-to-house cluster random sample surveys in evaluation units, which generally correspond to "health district" size: populations of 100,000-250,000 people. In each evaluation unit, we invite all residents aged 1 year and older from h households in each of c clusters to be examined for clinical signs of trachoma, where h is the number of households that can be seen by 1 team in 1 day, and the product h × c is calculated to facilitate recruitment of 1019 children aged 1-9 years. In addition to individual-level demographic and clinical data, household-level water, sanitation and hygiene data are entered into the purpose-built LINKS application on Android smartphones, transmitted to the Cloud, and cleaned, analyzed and ministry-of-health-approved via a secure web-based portal. The main outcome measures are the evaluation unit-level prevalence of follicular trachoma in children aged 1-9 years, prevalence of trachomatous trichiasis in adults aged 15 + years, percentage of households using safe methods for disposal of human feces, and percentage of households with proximate access to water for personal hygiene purposes. RESULTS: In the first year of fieldwork, 347 field teams commenced work in 21 projects in 7 countries. CONCLUSION: With an approach that is innovative in design and scale, we aim to complete baseline mapping of trachoma throughout the world in 2015
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