1,863 research outputs found

    Performance Analysis of Angle of Arrival Algorithms Applied to Radiofrequency Interference Direction Finding

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    Radiofrequency (RF) interference threatens the functionality of systems that increasingly underpin the daily function of modern society. In recent years there have been multiple incidents of intentional RF spectrum denial using terrestrial interference sources. Because RF based systems are used in safety-of-life applications in both military and civilian contexts, there is need for systems that can quickly locate these interference sources. In order to meet this need, the Air Force Research Laboratory Weapons Directorate is sponsoring the following research to support systems that will be able to quickly geolocate RF interferers using passive angle-of-arrival estimation to triangulate interference sources. This research studies the performance of angle-of arrival (AoA) estimation algorithms for an existing uniform linear antenna array. Four algorithms are presented, they are phase-shift beamforming, Capon or Minimum Variance Distortionless Response (MVDR) beamforming, the Multiple Signal Identification and Classification (MUSIC) algorithm, and one instantiation of a Maximum Likelihood Estimation (MLE) algorithm. A modeling and simulation environment using MATLAB™ is developed and the performance of each algorithm is simulated as implemented on a uniform linear array. Performance is characterized under various non-ideal conditions

    Using intervention mapping to develop a culturally appropriate intervention to prevent childhood obesity: the HAPPY (Healthy and Active Parenting Programme for Early Years) study.

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    INTRODUCTION: Interventions that make extensive use of theory tend to have larger effects on behaviour. The Intervention Mapping (IM) framework incorporates theory into intervention design, implementation and evaluation, and was applied to the development of a community-based childhood obesity prevention intervention for a multi-ethnic population. METHODS: IM was applied as follows: 1) Needs assessment of the community and culture; consideration of evidence-base, policy and practice; 2) Identification of desired outcomes and change objectives following identification of barriers to behaviour change mapped alongside psychological determinants (e.g. knowledge, self-efficacy, intention); 3) Selection of theory-based methods and practical applications to address barriers to behaviour change (e.g., strategies for responsive feeding); 4) Design of the intervention by developing evidence-based interactive activities and resources (e.g., visual aids to show babies stomach size). The activities were integrated into an existing parenting programme; 5) Adoption and implementation: parenting practitioners were trained by healthcare professionals to deliver the programme within Children Centres. RESULTS: HAPPY (Healthy and Active Parenting Programme for Early Years) is aimed at overweight and obese pregnant women (BMI > 25); consists of 12 × 2.5 hr. sessions (6 ante-natal from 24 weeks; 6 postnatal up to 9 months); it addresses mother's diet and physical activity, breast or bottle feeding, infant diet and parental feeding practices, and infant physical activity. CONCLUSION: We have demonstrated that IM is a feasible and helpful method for providing an evidence based and theoretical structure to a complex health behaviour change intervention. The next stage will be to assess the impact of the intervention on behaviour change and clinical factors associated with childhood obesity. The HAPPY programme is currently being tested as part of a randomised controlled feasibility trial

    Finding AGN in Deep X-ray Flux States with Swift

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    We report on our ongoing project of finding Active Galactic Nuclei (AGN) that go into deep X-ray flux states detected by Swift. Swift is performing an extensive study on the flux and spectral variability of AGN using Guest Investigator and team fill-in programs followed by triggering XMM_Newton for deeper follow-up observations. So far this program has been very successful and has led to a number of XMM-Newton follow up observations, including Mkn 335, PG 0844+349, and RX J2340.8-5329. Recent analysis of new Swift AGN observations reveal several AGN went into a very low X-ray flux state, particularly Narrow-Line Seyfert 1 galaxies. One of these is RX J2317-4422, which dropped by a factor of about 60 when compared to the ROSAT All-Sky Survey.Comment: 6 pages, 3 figures, Proceedings of the "10 Years of Swift" Meeting held in Rome in December 2014. Submitted to Po

    Classification tree methods for panel data using wavelet-transformed time series

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    Wavelet-transformed variables can have better classification performance for panel data than using variables on their original scale. Examples are provided showing the types of data where using a wavelet-based representation is likely to improve classification accuracy. Results show that in most cases wavelet-transformed data have better or similar classification accuracy to the original data, and only select genuinely useful explanatory variables. Use of wavelet-transformed data provides localized mean and difference variables which can be more effective than the original variables, provide a means of separating “signal” from “noise”, and bring the opportunity for improved interpretation via the consideration of which resolution scales are the most informative. Panel data with multiple observations on each individual require some form of aggregation to classify at the individual level. Three different aggregation schemes are presented and compared using simulated data and real data gathered during liver transplantation. Methods based on aggregating individual level data before classification outperform methods which rely solely on the combining of time-point classifications

    Study protocol: A multi-centre, double blind, randomised, placebo-controlled, parallel group, phase II trial (RIDD) to determine the efficacy of intra-nodular injection of anti-TNF to control disease progression in early Dupuytren’s disease, with an embedded dose response study. [version 2; peer review: 2 approved]

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    Dupuytren’s disease is a common fibrotic condition of the hand affecting 4% of the population and causes the fingers to curl irreversibly into the palm. It has a strong familial tendency, there is no approved treatment for early stage disease, and patients with established digital contractures are most commonly treated by surgery. This is associated with prolonged recovery, and less invasive techniques have high recurrence rates. The myofibroblasts, the cells responsible for the excessive matrix deposition and contraction, are aggregated in nodules. Using excised diseased and control human tissue, we found that immune cells interspersed amongst the myofibroblasts secrete cytokines. Of these, only tumour necrosis factor (TNF) promoted the development of myofibroblasts. The clinically approved anti-TNF agents led to inhibition of the myofibroblast phenotype in vitro. This clinical trial is designed to assess the efficacy of the anti-TNF agent adalimumab on participants with early disease. The first part is a dose-ranging study where nodules of participants already scheduled for surgery will be injected with either placebo (saline) or varying doses of adalimumab. The excised tissue will then be analysed for markers of myofibroblast activity. The second part of the study will recruit participants with early stage disease. They will be randomised 1: 1 to receive either adalimumab or placebo at 3 month intervals over 1 year and will then be followed for a further 6 months. Outcome measures will include nodule hardness, size and disease progression. The trial will also determine the cost-effectiveness of adalimumb treatment for this group of participants

    Description of the BRIGHTLIGHT cohort: the evaluation of teenage and young adult cancer services in England

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    Objective International recognition of the unique needs of young people with cancer is growing. Many countries have developed specialist age-appropriate cancer services believing them to be of value. In England, 13 specialist principal treatment centres (PTCs) deliver cancer care to young people. Despite this expansion of specialist care, systematic investigation of associated outcomes and costs has, to date, been lacking. The aim of this paper is to describe recruitment and baseline characteristics of the BRIGHTLIGHT cohort and the development of the bespoke measures of levels of care and disease severity, which will inform the evaluation of cancer services in England. Design Prospective, longitudinal, observational study. Setting Ninety-seven National Health Service hospitals in England. Participants A total of 1114 participants were recruited and diagnosed between July 2012 and December 2014: 55% (n=618) were men, mean age was 20.1 years (SD=3.3), most (86%) were white and most common diagnoses were lymphoma (31%), germ cell tumour (19%) and leukaemia (13%). Results At diagnosis, median quality of life score was significantly lower than a published control threshold (69.7 points); 40% had borderline to severe anxiety, and 21% had borderline to severe depression. There was minimal variation in other patient-reported outcomes according to age, diagnosis or severity of illness. Survival was lower in the cohort than for young people diagnosed during the same period who were not recruited (cumulative survival probability 4 years after diagnosis: 88% vs 92%). Conclusions Data collection was completed in March 2018. Longitudinal comparisons will determine outcomes and costs associated with access/exposure to PTCs. Findings will inform international intervention and policy initiatives to improve outcomes for young people with cancer

    Specialist cancer services for teenagers and young adults in England: BRIGHTLIGHT research programme

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    Background: When cancer occurs in teenagers and young adults, the impact is far beyond the physical disease and treatment burden. The effect on psychological, social, educational and other normal development can be profound. In addition, outcomes including improvements in survival and participation in clinical trials are poorer than in younger children and older adults with similar cancers. These unique circumstances have driven the development of care models specifically for teenagers and young adults with cancer, often focused on a dedicated purpose-designed patient environments supported by a multidisciplinary team with expertise in the needs of teenagers and young adults. In England, this is commissioned by NHS England and delivered through 13 principal treatment centres. There is a lack of evaluation that identifies the key components of specialist care for teenagers and young adults, and any improvement in outcomes and costs associated with it. / Objective: To determine whether or not specialist services for teenagers and young adults with cancer add value. / Design: A series of multiple-methods studies centred on a prospective longitudinal cohort of teenagers and young adults who were newly diagnosed with cancer. / Settings: Multiple settings, including an international Delphi study of health-care professionals, qualitative observation in specialist services for teenagers and young adults, and NHS trusts. / Participants: A total of 158 international teenage and young adult experts, 42 health-care professionals from across England, 1143 teenagers and young adults, and 518 caregivers. / Main outcome measures: The main outcomes were specific to each project: key areas of competence for the Delphi survey; culture of teenagers and young adults care in the case study; and unmet needs from the caregiver survey. The primary outcome for the cohort participants was quality of life and the cost to the NHS and patients in the health economic evaluation. / Data sources: Multiple sources were used, including responses from health-care professionals through a Delphi survey and face-to-face interviews, interview data from teenagers and young adults, the BRIGHTLIGHT survey to collect patient-reported data, patient-completed cost records, hospital clinical records, routinely collected NHS data and responses from primary caregivers. / Results: Competencies associated with specialist care for teenagers and young adults were identified from a Delphi study. The key to developing a culture of teenage and young adult care was time and commitment. An exposure variable, the teenagers and young adults Cancer Specialism Scale, was derived, allowing categorisation of patients to three groups, which were defined by the time spent in a principal treatment centre: SOME (some care in a principal treatment centre for teenagers and young adults, and the rest of their care in either a children’s or an adult cancer unit), ALL (all care in a principal treatment centre for teenagers and young adults) or NONE (no care in a principal treatment centre for teenagers and young adults). The cohort study showed that the NONE group was associated with superior quality of life, survival and health status from 6 months to 3 years after diagnosis. The ALL group was associated with faster rates of quality-of-life improvement from 6 months to 3 years after diagnosis. The SOME group was associated with poorer quality of life and slower improvement in quality of life over time. Economic analysis revealed that NHS costs and travel costs were similar between the NONE and ALL groups. The ALL group had greater out-of-pocket expenses, and the SOME group was associated with greater NHS costs and greater expense for patients. However, if caregivers had access to a principal treatment centre for teenagers and young adults (i.e. in the ALL or SOME groups), then they had fewer unmet support and information needs. / Limitations: Our definition of exposure to specialist care using Hospital Episode Statistics-determined time spent in hospital was insufficient to capture the detail of episodes or account for the variation in specialist services. Quality of life was measured first at 6 months, but an earlier measure may have shown different baselines. / Conclusions: We could not determine the added value of specialist cancer care for teenagers and young adults as defined using the teenage and young adult Cancer Specialism Scale and using quality of life as a primary end point. A group of patients (i.e. those defined as the SOME group) appeared to be less advantaged across a range of outcomes. There was variation in the extent to which principal treatment centres for teenagers and young adults were established, and the case study indicated that the culture of teenagers and young adults care required time to develop and embed. It will therefore be important to establish whether or not the evolution in services since 2012–14, when the cohort was recruited, improves quality of life and other patient-reported and clinical outcomes. / Future work: A determination of whether or not the SOME group has similar or improved quality of life and other patient-reported and clinical outcomes in current teenage and young adult service delivery is essential if principal treatment centres for teenagers and young adults are being commissioned to provide ‘joint care’ models with other providers. / Funding: This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 12. See the NIHR Journals Library website for further project information

    Smart Cities: Towards a New Citizenship Regime? A Discourse Analysis of the British Smart City Standard

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    Growing practice interest in smart cities has led to calls for a less technology-oriented and more citizen-centric approach. In response, this articles investigates the citizenship mode promulgated by the smart city standard of the British Standards Institution. The analysis uses the concept of citizenship regime and a mixture of quantitative and qualitative methods to discern key discursive frames defining the smart city and the particular citizenship dimensions brought into play. The results confirm an explicit citizenship rationale guiding the smart city (standard), although this displays some substantive shortcomings and contradictions. The article concludes with recommendations for both further theory and practice development

    The abolition of the General Teaching Council for England and the future of teacher discipline

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    With the abolition of the General Teaching Council for England in the 2011 Education Act, this article considers the future of teacher discipline in England. It provides a critique of the changes to the regulation of teacher misconduct and incompetence that draws on a Foucauldian framework, especially concerning the issue of public displays of discipline and the concomitant movement to more hidden forms. In addition, the external context of accountability that accompanies the reforms to teacher discipline are considered including the perfection of the panoptic metaphor presented by the changes to Ofsted practices such as the introduction of zero-notice inspections. The article concludes that the reforms will further move teachers from being occupational professionals to being organisational professionals marking them apart from comparable professions in medicine and law
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