Square vortex lattice at anomalously low magnetic fields in electron-doped Nd1.85_{1.85}Ce0.15_{0.15}CuO4_{4}

We report here on the first direct observations of the vortex lattice in the bulk of electron-doped Nd$_{1.85}$Ce$_{0.15}$CuO$_{4}$ single crystals. Using small angle neutron scattering, we have observed a square vortex lattice with the nearest-neighbors oriented at 45$^{\circ}$ from the Cu-O bond direction, which is consistent with theories based on the d-wave superconducting gap. However, the square symmetry persists down to unusually low magnetic fields. Moreover, the diffracted intensity from the vortex lattice is found to decrease rapidly with increasing magnetic field.Comment: 4 pages, 4 Figures, accepted for publication in Phys. Rev. Let

Colonisation of native tree and shrub plantings by woodland birds in an agricultural landscape

Tree planting has become a cornerstone strategy for natural resource management in agricultural landscapes, yet its contribution as habitat for woodland birds has not been fully investigated. A case study from the Holbrook region in southern New South Wales was used to assess woodland birds in young plantings of native trees and shrubs. Ground-foraging insectivorous woodland birds were under-represented in the plantings, partly due to a lack of native forb diversity (wildflowers) and leaf litter. Of 69 woodland bird species recorded over a three-year period, 48 species (70%) occurred in planted sites, 59 species (86%) occurred in remnant woodland, and 34 species (49%) occurred in adjacent paddock sites. The greater diversity of birds in planted sites relative to paddock sites was mostly due to understorey birds. The proportion of mist-netted birds recaptured was similar in both planted (15%) and remnant woodland (16%) sites, suggesting that individual birds were staying in planted sites. The proportion of woodland birds showing breeding activity (as measured by the presence of a brood patch) was slightly lower in planted sites (24% of all woodland species) than in remnant woodland (29%). Birds such as the superb fairy-wren, red-browed finch and southern whiteface were more likely to occur in planted sites, suggesting that plantings provide unique, transitional-stage habitat within agricultural landscapes. Restoring native forbs, as part of a broader strategy of woodland management, will help to reverse the decline of ground-foraging insectivorous woodland birds in agricultural landscapes

An online clinical decision tool to screen for vertebral fragility fractures (Vfrac) in older women presenting with back pain in general practice: protocol for a feasibility study in preparation for a future cluster randomised controlled trial

Summary: This feasibility study for a future definitive randomized trial assesses the use and acceptability of a new clinical decision tool to identify risk of a vertebral fracture and those who should be referred for spinal radiography in women aged 65 or over presenting to primary care with back pain. Purpose: Approximately 12% of older adults have vertebral fragility fractures, but currently fewer than one-third are diagnosed, potentially limiting access to bone protection treatment. Vfrac is a vertebral fracture screening tool which classifies individuals into high or low risk of having a vertebral fracture, allowing targeting of spinal radiographs to high-risk individuals. The objective of this study was to investigate the feasibility of conducting a cluster randomized controlled trial to evaluate the use of an online version of Vfrac in primary care. Methods: The study will run in six general practices, with three given the Vfrac tool for use on older women (> 65 years) consulting with back pain and three using standard clinical processes for managing such back pain. Anonymised data covering a 12-month period will be collected from all sites on consultations by older women with back pain. Focus groups will be undertaken with healthcare professionals and patients on whom the tool was used to understand the acceptability of Vfrac and identify factors that impact its use. These patients will be sent a paper version of the Vfrac questionnaire to self-complete at home. Outputs of the self-completion Vfrac (high versus low risk) will be compared with the face-to-face Vfrac (high versus low risk), and agreement assessed using Cohen’s kappa. Results: This study will evaluate the use and acceptability of Vfrac within primary care and determine if data on resource use can be collected accurately and comprehensively. Conclusions: This article describes the protocol of the Vfrac feasibility study. Trial registration: ISRCTN18000119 (registered 01/03/2022) and ISRCTN12150779 (registered 10/01/2022)

Driven vortices in type-II superconductors: A muon spin rotation study

We present a detailed study of vortex motion in a type-II superconductor using the muon spin rotation (μSR) technique. The vortices were set in motion by an alternating transport current. By adjusting the frequency and amplitude of the driving force so that vortices "visible" to the implanted muons did not cross the sample boundaries, a μSR line shape was obtained corresponding to almost perfectly ordered vortex motion. We also observed sidebands to the μSR line shape which correspond to the frequency at which vortices pass the implanted muon, and allow a direct measurement of the vortex velocity. Both these features of the line shape confirm numerical predictions reported in a previous study [see Charalambous, Phys. Rev. B 66, 054506 (2002)]. © 2006 The American Physical Society