21,705 research outputs found

    Scale-discretised ridgelet transform on the sphere

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    We revisit the spherical Radon transform, also called the Funk-Radon transform, viewing it as an axisymmetric convolution on the sphere. Viewing the spherical Radon transform in this manner leads to a straightforward derivation of its spherical harmonic representation, from which we show the spherical Radon transform can be inverted exactly for signals exhibiting antipodal symmetry. We then construct a spherical ridgelet transform by composing the spherical Radon and scale-discretised wavelet transforms on the sphere. The resulting spherical ridgelet transform also admits exact inversion for antipodal signals. The restriction to antipodal signals is expected since the spherical Radon and ridgelet transforms themselves result in signals that exhibit antipodal symmetry. Our ridgelet transform is defined natively on the sphere, probes signal content globally along great circles, does not exhibit blocking artefacts, supports spin signals and exhibits an exact and explicit inverse transform. No alternative ridgelet construction on the sphere satisfies all of these properties. Our implementation of the spherical Radon and ridgelet transforms is made publicly available. Finally, we illustrate the effectiveness of spherical ridgelets for diffusion magnetic resonance imaging of white matter fibers in the brain.Comment: 5 pages, 4 figures, matches version accepted by EUSIPCO, code available at http://www.s2let.or

    Refugee Resettlement in Crisis: The failure of the EU-Turkey Deal and the Case of Burden-Sharing

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    “A useful accessory to the infantry, but nothing more”: Tanks at the Battle of Flers-Courcelette, September 1916

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    The Battle of Flers-Courcelette is chiefly remembered as the combat introduction of tanks. The prevailing historiography maligns their performance as a lacklustre debut of a weapon which held so much promise for offensive warfare. However, unit war diaries and individual accounts of the battle suggest that the tank assaults of 15 September 1916 were far from total failures. This paper thus re-examines the role of tanks in the battle from the perspective of Canadian, British and New Zealand infantry. It finds that, rather than disappointing Allied combatants, the tanks largely lived up to their intended role of infantry support

    FITS - The File Information Tool Set

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    4th International Conference on Open RepositoriesThis presentation was part of the session : Conference PostersPreservation repositories include technical metadata for ingested files. The File Information Tool Set (FITS) is an open source tool that identifies, validates and extracts technical metadata for a wide range of file formats. It acts as a wrapper, invoking and managing the output from several other open source tools. Output from these tools are converted into a common format, compared to one another and consolidated into a single XML output file. FITS is written in Java and is compatible with Java 1.5 or higher. The external tools currently used are: JHOVE, Exiftool, National Library of New Zealand Metadata Extractor, DROID, FFIdent, and the unix File Utility.Harvard University Librar

    Smoking cessation activities by general practitioners and practice nurses

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    OBJECTIVES—To assess general practitioners' and practice nurses' self reported behaviour, attitudes, and knowledge in relation to smoking cessation.‹DESIGN AND SETTING—Two postal surveys of random national samples of 303 GPs (survey 1) and 459 practice nurses (survey 2) covering England and Wales; effective response rates were 75% and 96%, respectively.‹RESULTS—Survey 1 found that 96% of GPs accepted that intervening against smoking was part of their role and almost all (99%) said that they recorded smoking status when patients registered; 57% reported that they routinely updated their records on smoking status, 50% said they advised smokers to stop during most or all consultations, and 76% said they advised smokers to cut down if they cannot stop. A large majority (83%) said they either recommended or prescribed nicotine replacement therapy (NRT). Although most GPs (86%) thought that NRTs were effective, only a minority thought they were worth the cost (47%) or should be on National Health Service (NHS) prescription (32%). There was little evidence that previous training in smoking cessation was associated with more activity, more positive attitudes, or greater knowledge. Survey 2 found that almost all practice nurses (99%) agreed that intervening against smoking was part of their role and 95% said they advised patients to stop at least occasionally; 71% said they advised smokers to stop at most or all consultations. A majority (74%) said that they recommended NRT to their patients. As with the GPs most practice nurses thought that nicotine replacement was effective (79%), but fewer (42%) thought the cost was justified, and only about half (53%) thought it should be available on NHS prescription. Nurses who said they had been trained in smoking cessation engaged in more activity relating to smoking cessation, had more positive attitudes, and were more knowledgeable.‹CONCLUSION—GPs and practice nurses accepted that intervening with smoking was an important part of their role and a large majority reported that they intervened at least with some smokers. This represents a promising baseline from which to proceed in terms of implementation of the new smoking cessation guidelines, but it is hoped that improvements can be made in terms of the frequency of updating records and intervening, and acceptance of the cost-effectiveness of NRT as a life preserving intervention.‹‹‹Keywords: cessation interventions; general practitioners; practice nurse

    Fathers’ parenting, adverse life events, and adolescents’ emotional and eating disorder symptoms: the role of emotion regulation

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    Purpose: To investigate the role of emotion regulation in the relation between fathers’ parenting (specifically warmth, behavioral control and psychological control) and adolescents’ emotional and eating disorder symptoms, after adjustment for controls. Methods: A total of 203 11-18 year-old students from a school in a socio-economically disadvantaged area in North-East London completed questionnaires assessing emotional symptoms (measured with the Strengths and Difficulties Questionnaire’s (SDQ) Emotional Symptoms Scale), eating disorder symptoms (measured with the Eating Attitudes Test (EAT-26)), difficulties in emotion regulation (measured with the Difficulties in Emotion Regulation Scale (DERS)), and fathers’ overprotection and warmth, measured with the Parental Bonding Instrument (PBI), as well as behavioral and psychological control. The confounding variables considered were number of proximal (i.e., during the last year) adverse life events experienced, gender, age, and socio-economic status (eligibility for free school meals). Results: Adolescents’ difficulties in emotion regulation mediated the link between fathers’ psychological control and adolescents’ emotional symptoms, but not the link between fathers’ parenting and adolescents’ eating disorder symptoms, which appeared to be more directly linked to fathers’ psychological control and number of proximal adverse life events experienced. Proximal adverse life events experienced were also strongly associated with difficulties in emotion regulation. Conclusions: The study findings have implications for intervention programs which may prove more fruitful in addressing adolescent emotional problems by targeting underlying emotion regulation abilities, and in addressing adolescent eating disorder symptoms by protecting adolescents with a recent experience of multiple adverse life events. Parenting programs also stand to benefit from the evidence presented in this study that paternal psychological control may have uniquely harmful consequences for adolescent development through the hampering or atrophying of emotion regulation abilities and the encouragement of eating disorders

    SO2-rich equatorial basins and epeirogeny of Io

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    Comparison of Io's large scale topography with an SO2 abundance map shows that SO2 is concentrated in equatorial topographic basins. In these basins, about 30 pct. of the surface is covered by SO2 at all elevations above the mean triaxial figure, and SO2 coverage increases with decreasing elevation to as much as 56 pct. at elevations below -1.5 km. The correlation is not good from long 240 to 360 degs where bright areas are covered by red, Pele type plume fallout, and in the polar regions where the topography is poorly known. The histogram of SO2 abundance binned by elevation appears bimodal, with a secondary concentration of SO2 at high elevations, but it is not certain that this is significant. Additional observations suggest that the basins have relatively little higher frequency topographic relief. The distribution of active plumes and hotspots show no obvious correlation with the topography. However, the Pele type plume all erupted from regions higher than the mean figure, and five of the eight Prometheus type plumes are more energetic and are associated with high temperature hotspots, whereas Prometheus type plumes are long lived and require large volatile reservoirs
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