Diffractive orbits in isospectral billiards

Isospectral domains are non-isometric regions of space for which the spectra of the Laplace-Beltrami operator coincide. In the two-dimensional Euclidean space, instances of such domains have been given. It has been proved for these examples that the length spectrum, that is the set of the lengths of all periodic trajectories, coincides as well. However there is no one-to-one correspondence between the diffractive trajectories. It will be shown here how the diffractive contributions to the Green functions match nevertheless in a ''one-to-three'' correspondence.Comment: 20 pages, 6 figure

‘It’s better than daytime television’: questioning the socio-spatial impacts of massage parlours on residential communities

It has been shown that street sex work is problematic for some communities, but there is less evidence of the effects of brothels. Emerging research also suggests that impact discourses outlined by residential communities and in regulatory policies should be critiqued, because they are often based on minority community voices, and limited tangible evidence is used to masquerade wider moral viewpoints about the place of sex work. Using a study of residents living in close proximity to brothels in Blackpool, this paper argues that impact is socially and spatially fluid. Impact needs to be evaluated in a more nuanced manner, which is considerate of the heterogeneity of (even one type of) sex work, and the community in question. Brothels in Blackpool had a variety of roles in the everyday socio-spatial fabric; thus also questioning the common assumption that sex work only impacts negatively on residential communities

Progress in marine geoconservation in Scotland’s seas : assessment of key interests and their contribution to Marine Protected Area network planning

This study was part-funded by Marine Scotland and was undertaken as part of the Scottish Marine Protected Areas (MPA) Programme, a joint initiative between Marine Scotland, Historic Scotland, Scottish Natural Heritage (SNH) and the Joint Nature Conservation Committee (JNCC).Geoconservation in the marine environment has been largely overlooked, despite a wealth of accumulated information on marine geology and geomorphology and clear links between many terrestrial and marine features. As part of the wider characterisation of Scotland’s seas, this study developed criteria and a methodology that follow the established principles of the terrestrial, Great Britain-wide geoconservation audit, the Geological Conservation Review, to assess geodiversity key areas on the seabed. Using an expert judgement approach, eight geodiversity feature categories were identified to represent the geological and geomorphological processes that have influenced the evolution and present-day morphology of the Scottish seabed: Quaternary of Scotland; Submarine Mass Movement; Marine Geomorphology of the Scottish Deep-Ocean Seabed; Seabed Fluid and Gas Seep; Cenozoic Structures of the Atlantic Margin; Marine Geomorphology of the Scottish Shelf Seabed; Coastal Geomorphology of Scotland; and Biogenic Structures of the Scottish Seabed. Within these categories, 35 key areas were prioritised for their scientific value. Specific interests range from large-scale landforms (e.g. submarine landslides, sea-mounts and trenches) to fine-scale dynamic features (e.g. sand waves). Although these geodiversity interests provided supporting evidence for the identification and selection of a suite of Nature Conservation Marine Protected Areas (MPAs) containing important marine natural features, they are only partially represented in these MPAs and existing protected areas. Nevertheless, a pragmatic approach is emerging to integrate as far as possible the conservation management of marine geodiversity with that of biodiversity and based on evidence of the sensitivity and vulnerability geological and geomorphological features on the seabed.PostprintPeer reviewe

Protocol for the Foot in Juvenile Idiopathic Arthritis trial (FiJIA): a randomised controlled trial of an integrated foot care programme for foot problems in JIA

<b>Background</b>: Foot and ankle problems are a common but relatively neglected manifestation of juvenile idiopathic arthritis. Studies of medical and non-medical interventions have shown that clinical outcome measures can be improved. However existing data has been drawn from small non-randomised clinical studies of single interventions that appear to under-represent the adult population suffering from juvenile idiopathic arthritis. To date, no evidence of combined therapies or integrated care for juvenile idiopathic arthritis patients with foot and ankle problems exists. <b>Methods/design</b>: An exploratory phase II non-pharmacological randomised controlled trial where patients including young children, adolescents and adults with juvenile idiopathic arthritis and associated foot/ankle problems will be randomised to receive integrated podiatric care via a new foot care programme, or to receive standard podiatry care. Sixty patients (30 in each arm) including children, adolescents and adults diagnosed with juvenile idiopathic arthritis who satisfy the inclusion and exclusion criteria will be recruited from 2 outpatient centres of paediatric and adult rheumatology respectively. Participants will be randomised by process of minimisation using the Minim software package. The primary outcome measure is the foot related impairment measured by the Juvenile Arthritis Disability Index questionnaire's impairment domain at 6 and 12 months, with secondary outcomes including disease activity score, foot deformity score, active/limited foot joint counts, spatio-temporal and plantar-pressure gait parameters, health related quality of life and semi-quantitative ultrasonography score for inflammatory foot lesions. The new foot care programme will comprise rapid assessment and investigation, targeted treatment, with detailed outcome assessment and follow-up at minimum intervals of 3 months. Data will be collected at baseline, 6 months and 12 months from baseline. Intention to treat data analysis will be conducted. A full health economic evaluation will be conducted alongside the trial and will evaluate the cost effectiveness of the intervention. This will consider the cost per improvement in Juvenile Arthritis Disability Index, and cost per quality adjusted life year gained. In addition, a discrete choice experiment will elicit willingness to pay values and a cost benefit analysis will also be undertaken

On our own terms : the working conditions of internet-based sex workers in the UK

The sex industry is increasingly operated through online technologies, whether this is selling services online through webcam or advertising, marketing or organising sex work through the Internet and digital technologies. Using data from a survey of 240 internet-based sex workers (members of the National Ugly Mug reporting scheme in the UK), we discuss the working conditions of this type of work. We look at the basic working patterns, trajectories and everyday experiences of doing sex work via an online medium and the impact this has on the lives of sex workers. For instance, we look at levels of control individuals have over their working conditions, prices, clientele and services sold, and discuss how this is mediated online and placed in relation to job satisfaction. The second key finding is the experience of different forms of crimes individuals are exposed to such as harassment and blackmail via the new technologies. We explore the relationship internet-based sex workers have with the police and discuss how current laws in the UK have detrimental effects in terms of safety and access to justice. These findings are placed in the context of the changing landscape of sex markets as the digital turn determines the nature of the majority of commercial sex encounters. These findings contribute significantly to the populist coercion/choice political debates by demonstrating levels and types of agency and autonomy experienced by some sex workers despite working in a criminalized, precarious and sometimes dangerous context

Search for medium modification of the ρ\rho meson

The photoproduction of vector mesons on various nuclei has been studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory. The vector mesons, $\rho$, $\omega$, and $\phi$, are observed via their decay to $e^+e^-$, in order to reduce the effects of final state interactions in the nucleus. Of particular interest are possible in-medium effects on the properties of the $\rho$ meson. The $\rho$ spectral function is extracted from the data on various nuclei, carbon, iron, and titanium, and compared to the spectrum from liquid deuterium, which is relatively free of nuclear effects. We observe no significant mass shift for the $\rho$ meson; however, there is some widening of the resonance in titanium and iron, which is consistent with expected collisional broadening.Comment: 8 pages, 4 figure

The youngest massive protostars in the Large Magellanic Cloud

We demonstrate the unique capabilities of Herschel to study very young luminous extragalactic young stellar objects (YSOs) by analyzing a central strip of the Large Magellanic Cloud obtained through the HERITAGE Science Demonstration Program. We combine PACS 100 and 160, and SPIRE 250, 350, and 500 microns photometry with 2MASS (1.25-2.17 microns) and Spitzer IRAC and MIPS (3.6-70 microns) to construct complete spectral energy distributions (SEDs) of compact sources. From these, we identify 207 candidate embedded YSOs in the observed region, ~40% never-before identified. We discuss their position in far-infrared color-magnitude space, comparing with previously studied, spectroscopically confirmed YSOs and maser emission. All have red colors indicating massive cool envelopes and great youth. We analyze four example YSOs, determining their physical properties by fitting their SEDs with radiative transfer models. Fitting full SEDs including the Herschel data requires us to increase the size and mass of envelopes included in the models. This implies higher accretion rates (greater than or equal to 0.0001 M_sun/yr), in agreement with previous outflow studies of high-mass protostars. Our results show that Herschel provides reliable longwave SEDs of large samples of high-mass YSOs; discovers the youngest YSOs whose SEDs peak in Herschel bands; and constrains the physical properties and evolutionary stages of YSOs more precisely than was previously possible.Comment: Main text: 4 pages, 3 figures, 1 table; Online material: 3 figures, 1 table; to appear in the A&A Herschel Special Issu

Measurement of Inclusive Spin Structure Functions of the Deuteron

We report the results of a new measurement of spin structure functions of the deuteron in the region of moderate momentum transfer ($Q^2$ = 0.27 -- 1.3 (GeV/c)$^2$) and final hadronic state mass in the nucleon resonance region ($W$ = 1.08 -- 2.0 GeV). We scattered a 2.5 GeV polarized continuous electron beam at Jefferson Lab off a dynamically polarized cryogenic solid state target ($^{15}$ND$_3$) and detected the scattered electrons with the CEBAF Large Acceptance Spectrometer (CLAS). From our data, we extract the longitudinal double spin asymmetry $A_{||}$ and the spin structure function $g_1^d$. Our data are generally in reasonable agreement with existing data from SLAC where they overlap, and they represent a substantial improvement in statistical precision. We compare our results with expectations for resonance asymmetries and extrapolated deep inelastic scaling results. Finally, we evaluate the first moment of the structure function $g_1^d$ and study its approach to both the deep inelastic limit at large $Q^2$ and to the Gerasimov-Drell-Hearn sum rule at the real photon limit ($Q^2 \to 0$). We find that the first moment varies rapidly in the $Q^2$ range of our experiment and crosses zero at $Q^2$ between 0.5 and 0.8 (GeV/c)$^2$, indicating the importance of the $\Delta$ resonance at these momentum transfers.Comment: 13 pages, 8 figures, ReVTeX 4, final version as accepted by Phys. Rev.

First measurement of coherent ϕ\phi-meson photoproduction on deuteron at low energies

The cross section and decay angular distributions for the coherent \phi meson photoproduction on the deuteron have been measured for the first time up to a squared four-momentum transfer t =(p_{\gamma}-p_{\phi})^2 =-2 GeV^2/c^2, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The cross sections are compared with predictions from a re-scattering model. In a framework of vector meson dominance, the data are consistent with the total \phi-N cross section \sigma_{\phi N} at about 10 mb. If vector meson dominance is violated, a larger \sigma_{\phi N} is possible by introducing larger t-slope for the \phi N \to \phi N process than that for the \gamma N \to \phi N process. The decay angular distributions of the \phi are consistent with helicity conservation.Comment: 6 page

Electroproduction of ϕ(1020)\phi(1020) mesons at 1.4≤Q2≤1.4\leq Q^2\leq GeV2^2 measured with the CLAS spectrometer

Electroproduction of exclusive $\phi$ vector mesons has been studied with the CLAS detector in the kinematical range $1.4\leq Q^2\leq 3.8$ GeV$^{2}$, $0.0\leq t^{\prime}\leq 3.6$ GeV$^{2}$, and $2.0\leq W\leq 3.0$ GeV. The scaling exponent for the total cross section as $1/(Q^2+M_{\phi}^2)^n$ was determined to be $n=2.49\pm 0.33$. The slope of the four-momentum transfer $t'$ distribution is $b_{\phi}=0.98 \pm 0.17$ GeV$^{-2}$. Under the assumption of s-channel helicity conservation (SCHC), we determine the ratio of longitudinal to transverse cross sections to be $R=0.86 \pm 0.24$. A 2-gluon exchange model is able to reproduce the main features of the data.Comment: Phys Rev C, 15 pages, 18 figure