Surface acoustic wave-induced electroluminescence intensity oscillation in planar light-emitting devices

Electroluminescence emission from surface acoustic wave-driven light-emitting diodes (SAWLEDs) is studied by means of time-resolved techniques. We show that the intensity of the SAW-induced electroluminescence is modulated at the SAW frequency (~1 GHz), demonstrating electron injection into the p-type region synchronous with the SAW wavefronts.Comment: 4 pages, 3 figure

The identification of Theileria bicornis in captive rhinoceros in Australia

© 2018 Poaching of both black (Diceros bicornis) and white (Ceratotherium simum) rhinoceros in Africa has increased significantly in recent years. In an effort to ensure the survival of these critically endangered species, breeding programs were established in the 1990s in Australia, where a similar climate and habitat is available. In this study we examined blood samples from two C. simum, including a 16 yr old female (Aluka) who died in captivity, and a 17 yr old asymptomatic male (Umfana). Bloods from seven healthy D. bicornis housed at the zoo were also collected. All samples were tested for the presence of piroplasms via blood smear and PCR. A generic PCR for the 18S rRNA gene of the Piroplasmida revealed the presence of piroplasm infection in both dead and asymptomatic C. simum. Subsequent sequencing of these amplicons revealed the presence of Theileria bicornis. Blood smear indicated that this organism was present at low abundance in both affected and asymptomatic individuals and was not linked to the C. simum mortality. T. bicornis was also detected in the D. bicornis population (n = 7) housed at Taronga Western Plains Zoo using PCR and blood film examination; however only animals imported from Africa (n = 1) tested T. bicornis positive, while captive-born animals bred within Australia (n = 6) tested negative suggesting that transmission within the herd was unlikely. Phylogenetic analysis of the full length T. bicornis 18S rRNA genes classified this organism outside the clade of the transforming and non-transforming Theileria with a new haplotype, H4, identified from D. bicornis. This study revealed the presence of Theileria bicornis in Australian captive populations of both C. simum and D. bicornis and a new haplotype of the parasite was identified

Graphene formation on SiC substrates

Graphene layers were created on both C and Si faces of semi-insulating, on-axis, 4H- and 6H-SiC substrates. The process was performed under high vacuum (<10-4 mbar) in a commercial chemical vapor deposition SiC reactor. A method for H2 etching the on-axis sub-strates was developed to produce surface steps with heights of 0.5 nm on the Si-face and 1.0 to 1.5 nm on the C-face for each polytype. A process was developed to form graphene on the substrates immediately after H2 etching and Raman spectroscopy of these samples confirmed the formation of graphene. The morphology of the graphene is described. For both faces, the underlying substrate morphology was significantly modified during graphene formation; sur-face steps were up to 15 nm high and the uniform step morphology was sometimes lost. Mo-bilities and sheet carrier concentrations derived from Hall Effect measurements on large area (16 mm square) and small area (2 and 10 um square) samples are presented and shown to compare favorably to recent reports.Comment: European Conference on Silicon Carbide and Related Materials 2008 (ECSCRM '08), 4 pages, 4 figure

Knot soliton in Weinberg-Salam model

We study numerically the topological knot solution suggested recently in the Weinberg-Salam model. Applying the SU(2) gauge invariant Abelian projection we demonstrate that the restricted part of the Weinberg-Salam Lagrangian containing the interaction of the neutral boson with the Higgs scalar can be reduced to the Ginzburg-Landau model with the hidden SU(2) symmetry. The energy of the knot composed from the neutral boson and Higgs field has been evaluated by using the variational method with a modified Ward ansatz. The obtained numerical value is 39 Tev which provides the upper bound on the electroweak knot energy.Comment: 6 pages, 3 figures, analysis of stability adde

Statistical properties of exoplanets III. Planet properties and stellar multiplicity

Among the hundred or so extrasolar planets discovered to date, 19 are orbiting a component of a double or multiple star system. In this paper, we discuss the properties of these planets and compare them to the characteristics of planets orbiting isolated stars. Although the sample of planets found in multiple star systems is not large, some differences between the orbital parameters and the masses of these planets and the ones of planets orbiting single stars are emerging in the mass-period and in the eccentricity-period diagrams. As pointed out by Zucker & Mazeh (2002), the most massive short-period planets are all found in multiple star systems. We show here that the planets orbiting in multiple star systems also tend to have a very low eccentricity when their period is shorter than about 40 days. These observations seem to indicate that some kind of migration has been at work in the history of these systems. The properties of the five short-period planets orbiting in multiple star systems seem, however, difficult to explain with the current models of planet formation and evolution, at least if we want to invoke a single mechanism to account for all the characteristics of these planets.Comment: 9 pages, 2 figures, accepted for publication in A&

From Cambridge Keynesian to Institutional Economist: The Unnoticed Contributions of Robert Neild

This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.Robert Neild (born 1924) has made a major contribution to economics and to peace studies. This paper provides a brief sketch of Neild’s life and work. While noting his research in economic policy and peace studies, this essay devotes more attention to his largely-unnoticed contributions to institutional and evolutionary economics since 1984. These are important in their own right, but they are especially notable because Cambridge heterodox economists have been devoted mainly to other approaches, including Marxism and post-Keynesianism. Neild’s distinctive contribution is partly explained by his closeness to both Nicholas Kaldor and Gunnar Myrdal. Myrdal made explicit his adherence to the original American institutionalism: Neild extended that link to Cambridge.Peer reviewedFinal Published versio

What’s Sex (Composition) Got to Do with It? The Importance of Sex Composition of Gangs for Female and Male Members’ Offending and Victimization

Sex composition of groups has been theorized in organizational sociology and found in prior work to structure female and male members’ behaviors and experiences. Peer group and gang literature similarly finds that the sex gap in offending varies across groups of differing sex ratios. Drawing on this and other research linking gang membership, offending, and victimization, we examine whether sex composition of gangs is linked to sex differences in offending in this sample, further assess whether sex composition similarly structures females’ and males’ victimization experiences, and if so, why. Self-report data from gang members in a multi-site, longitudinal study of 3,820 youths are employed. Results support previous findings about variations in member delinquency by both sex and sex composition of the gang and also indicate parallel variations in members’ victimization. These results are further considered within the context of facilitating effects such as gender dynamics, gang characteristics, and normative orientation

NAP SACC UK:protocol for a feasibility cluster randomised controlled trial in nurseries and at home to increase physical activity and healthy eating in 2-4 year olds

Introduction: Systematic reviews have identified the lack of intervention studies with young children to prevent obesity. This feasibility study examines the feasibility and acceptability of adapting the Nutrition and Physical Activity Self-Assessment for Child Care (NAP SACC) intervention in the UK to inform a full-scale trial. Methods and analysis: A feasibility cluster randomised controlled trial in 12 nurseries in England, with 6 randomly assigned to the adapted NAP SACC UK intervention: nursery staff will receive training and support from an NAP SACC UK Partner to review the nursery environment (nutrition, physical activity, sedentary behaviours and oral health) and set goals for making changes. Parents will be invited to participate in a digital media-based home component to set goals for making changes in the home. As this is a feasibility study, the sample size was not based on a power calculation but will indicate the likely response rates and intracluster correlations. Measures will be assessed at baseline and 8–10 months later. We will estimate the recruitment rate of nurseries and children and adherence to the intervention and data. Nursery measurements will include the Environmental Policy Assessment and Observation score and the nursery staff's review of the nursery environment. Child measurements will include height and weight to calculate z-score body mass index (zBMI), accelerometer-determined minutes of moderate-to-vigorous physical activity per day and sedentary time, and diet using the Child and Diet Evaluation Tool. Questionnaires with nursery staff and parents will measure mediators. A process evaluation will assess fidelity of intervention delivery and views of participants. Ethics and dissemination: Ethical approval for this study was given by Wales 3 NHS Research Ethics Committee. Findings will be made available through publication in peer-reviewed journals, at conferences and to participants via the University of Bristol website. Data will be available from the University of Bristol Research Data Repository

Exploring the equity of GP practice prescribing rates for selected coronary heart disease drugs: a multiple regression analysis with proxies of healthcare need

Background There is a small, but growing body of literature highlighting inequities in GP practice prescribing rates for many drug therapies. The aim of this paper is to further explore the equity of prescribing for five major CHD drug groups and to explain the amount of variation in GP practice prescribing rates that can be explained by a range of healthcare needs indicators (HCNIs). Methods The study involved a cross-sectional secondary analysis in four primary care trusts (PCTs 1–4) in the North West of England, including 132 GP practices. Prescribing rates (average daily quantities per registered patient aged over 35 years) and HCNIs were developed for all GP practices. Analysis was undertaken using multiple linear regression. Results Between 22–25% of the variation in prescribing rates for statins, beta-blockers and bendrofluazide was explained in the multiple regression models. Slightly more variation was explained for ACE inhibitors (31.6%) and considerably more for aspirin (51.2%). Prescribing rates were positively associated with CHD hospital diagnoses and procedures for all drug groups other than ACE inhibitors. The proportion of patients aged 55–74 years was positively related to all prescribing rates other than aspirin, where they were positively related to the proportion of patients aged >75 years. However, prescribing rates for statins and ACE inhibitors were negatively associated with the proportion of patients aged >75 years in addition to the proportion of patients from minority ethnic groups. Prescribing rates for aspirin, bendrofluazide and all CHD drugs combined were negatively associated with deprivation. Conclusion Although around 25–50% of the variation in prescribing rates was explained by HCNIs, this varied markedly between PCTs and drug groups. Prescribing rates were generally characterised by both positive and negative associations with HCNIs, suggesting possible inequities in prescribing rates on the basis of ethnicity, deprivation and the proportion of patients aged over 75 years (for statins and ACE inhibitors, but not for aspirin)