Outcomes of a pilot study in chiropractic practices in Western Australia

Background This paper reports the quantitative outcomes of a mixed-methods pilot study of the characteristics and demographics of chiropractic practices and patients in Western Australia. Methods This was a mixed-methods data transformation model (qualitative to quantitative) pilot study. A non-random sample of chiropractic practices across Western Australia was recruited and data collected anonymously from consecutive new patients using an online platform. Data covered practice and patient demographics and characteristics, alongside quality of life measures. A descriptive quantitative analysis characterised the sample, and the patient population was stratified by main reason for presentation to compare characteristics according to the presence of secondary complaints. Odds ratios were calculated to estimate the odds of a secondary complaint for various combinations of main complaints, from univariate logistic regression models. Results Of the 539 registered practitioners in WA in July 2014, 33 agreed to participate, from 20 different practices. Ten participating practices provided data on 325 adult new patients. The recruited practices (metropolitan n = 8, regional n = 2) had a positive response rate of 79.7 % (n = 301 metropolitan and n  = 24 regional patients), mean age 36.3 years (range 18–74) (53.2 % female). Spinal problems were reported as the main reason for consultation by 67 % and as secondary reasons by 77.2 % of patients. People presented primarily for health maintenance or a general health check in 11.4 %, and as a secondary reason 14.8 %. There were 30 % of people below societal norms for the SF-12 Physical Component Score (mean 47.19, 95 % CI; 46.27–48.19) and 86 % for the Mental Component Score (mean 36.64, 95 % CI; 35.93-37.65), Pain Impact Questionnaire mean scores were 54.60 (95 % CI; 53.32–55.88). Conclusions Patients presented to chiropractors in Western Australia with a fairly wide range of conditions, but primarily spinal and musculoskeletal-related problems. A significant proportion of patients had associated, or found to be at risk of, depression. Consequently, there are responsibilities and opportunities for chiropractors with respect to providing care services that include health promotion and well-being education related to musculoskeletal/spinal and mental health. This pilot study supports the feasibility of a future confirmatory study where the potential role of chiropractors in spinal/musculoskeletal health management may be explored

The Role of Surface Entropy in Statistical Emission of Massive Fragments from Equilibrated Nuclear Systems

Statistical fragment emission from excited nuclear systems is studied within the framework of a schematic Fermi-gas model combined with Weisskopf's detailed balance approach. The formalism considers thermal expansion of finite nuclear systems and pays special attention to the role of the diffuse surface region in the decay of hot equilibrated systems. It is found that with increasing excitation energy, effects of surface entropy lead to a systematic and significant reduction of effective emission barriers for fragments and, eventually, to the vanishing of these barriers. The formalism provides a natural explanation for the occurrence of negative nuclear heat capacities reported in the literature. It also accounts for the observed linearity of pseudo-Arrhenius plots of the logarithm of the fragment emission probability {\it versus} the inverse square-root of the excitation energy, but does not predict true Arrhenius behavior of these emission probabilities

Quantum superconductor-metal transition

We consider a system of superconducting grains embedded in a normal metal. At zero temperature this system exhibits a quantum superconductor-normal metal phase transition. This transition can take place at arbitrarily large conductance of the normal metal.Comment: 13 pages, 1 figure include

Quantum-fluctuation-induced repelling interaction of quantum string between walls

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Superconducting fluctuations and the Nernst effect: A diagrammatic approach

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Scaling in the Lattice Gas Model

A good quality scaling of the cluster size distributions is obtained for the Lattice Gas Model using the Fisher's ansatz for the scaling function. This scaling identifies a pseudo-critical line in the phase diagram of the model that spans the whole (subcritical to supercritical) density range. The independent cluster hypothesis of the Fisher approach is shown to describe correctly the thermodynamics of the lattice only far away from the critical point.Comment: 4 pages, 3 figure

The power of quantum systems on a line

We study the computational strength of quantum particles (each of finite dimensionality) arranged on a line. First, we prove that it is possible to perform universal adiabatic quantum computation using a one-dimensional quantum system (with 9 states per particle). This might have practical implications for experimentalists interested in constructing an adiabatic quantum computer. Building on the same construction, but with some additional technical effort and 12 states per particle, we show that the problem of approximating the ground state energy of a system composed of a line of quantum particles is QMA-complete; QMA is a quantum analogue of NP. This is in striking contrast to the fact that the analogous classical problem, namely, one-dimensional MAX-2-SAT with nearest neighbor constraints, is in P. The proof of the QMA-completeness result requires an additional idea beyond the usual techniques in the area: Not all illegal configurations can be ruled out by local checks, so instead we rule out such illegal configurations because they would, in the future, evolve into a state which can be seen locally to be illegal. Our construction implies (assuming the quantum Church-Turing thesis and that quantum computers cannot efficiently solve QMA-complete problems) that there are one-dimensional systems which take an exponential time to relax to their ground states at any temperature, making them candidates for being one-dimensional spin glasses.Comment: 21 pages. v2 has numerous corrections and clarifications, and most importantly a new author, merged from arXiv:0705.4067. v3 is the published version, with additional clarifications, publisher's version available at http://www.springerlink.co

Critical fluctuation conductivity in layered superconductors in strong electric field

The paraconductivity, originating from critical superconducting order-parameter fluctuations in the vicinity of the critical temperature in a layered superconductor is calculated in the frame of the self-consistent Hartree approximation, for an arbitrarily strong electric field and zero magnetic field. The paraconductivity diverges less steep towards the critical temperature in the Hartree approximation than in the Gaussian one and it shows a distinctly enhanced variation with the electric field. Our results indicate that high electric fields can be effectively used to suppress order-parameter fluctuations in high-temperature superconductors.Comment: 11 pages, 2 figures, to be published in Phys. Rev.

Destruction of diagonal and off-diagonal long range order by disorder in two-dimensional hard core boson systems

We use quantum Monte Carlo simulations to study the effect of disorder, in the form of a disordered chemical potential, on the phase diagram of the hard core bosonic Hubbard model in two dimensions. We find numerical evidence that in two dimensions, no matter how weak the disorder, it will always destroy the long range density wave order (checkerboard solid) present at half filling and strong nearest neighbor repulsion and replace it with a bose glass phase. We study the properties of this glassy phase including the superfluid density, energy gaps and the full Green's function. We also study the possibility of other localized phases at weak nearest neighbor repulsion, i.e. Anderson localization. We find that such a phase does not truly exist: The disorder must exceed a threshold before the bosons (at weak nn repulsion) are localized. The phase diagram for hard core bosons with disorder cannot be obtained easily from the soft core phase diagram discussed in the literature.Comment: 7 pages, 10 eps figures include

DC and AC Josephson Effect in a Superconductor-Luttinger Liquid-Superconductor System

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