Quantum States of Topologically Massive Electrodynamics and Gravity

The free quantum states of topologically massive electrodynamics and gravity in 2+1 dimensions, are explicitly found. It is shown that in both theories the states are described by infrared-regular polarization tensors containing a regularization phase which depends on the spin. This is done by explicitly realizing the quantum algebra on a functional Hilbert space and by finding the Wightman function to define the scalar product on such a Hilbert space. The physical properties of the states are analyzed defining creation and annihilation operators. For both theories, a canonical and covariant quantization procedure is developed. The higher order derivatives in the gravitational lagrangian are treated by means of a preliminary Dirac procedure. The closure of the Poincar\'e algebra is guaranteed by the infrared-finiteness of the states which is related to the spin of the excitations through the regularization phase. Such a phase may have interesting physical consequences.Comment: 21 page, latex, no figure

Psychosocial and treatment correlates of opiate free success in a clinical review of a naltrexone implant program

Background: There is on-going controversy in relation to the efficacy of naltrexone used for the treatment of heroin addiction, and the important covariates of that success. We were also interested to review our experience with two depot forms of implantable naltrexone. Methods: A retrospective review of patients' charts was undertaken, patients were recalled by telephone and by letter, and urine drug screen samples were collected. Opiate free success (OFS) was the parameter of interest. Three groups were defined. The first two were treated in the previous 12 months and comprised "implant" and "tablet" patients. A third group was "historical" comprising those treated orally in the preceding 12 months. Results: There were 102, 113 and 161 patients in each group respectively. Groups were matched for age, sex, and dose of heroin used, but not financial status or social support. The overall follow-up rate was 82%. The Kaplan Meier 12 month OFS were 82%, 58% and 52% respectively. 12 post-treatment variables were independently associated with treatment retention. In a Cox proportional hazard multivariate model social support, the number of detoxification episodes, post-treatment employment, the use of multiple implant episodes and spiritual belief were significantly related to OFS. Conclusion: Consistent with the voluminous international literature clinically useful retention rates can be achieved with naltrexone, which may be improved by implants and particularly serial implants, repeat detoxification, meticulous clinical follow-up, and social support. As depot formulations of naltrexone become increasingly available such results can guide their clinical deployment, improve treatment outcomes, and enlarge the policy options for an exciting non-addictive pharmacotherapy for opiate addiction

Determination of the ratio of b-quark fragmentation fractions fs/fd in pp collisions at √s = 7 TeV with the ATLAS Detector

With an integrated luminosity of 2.47  fb−1 recorded by the ATLAS experiment at the LHC, the exclusive decays B 0s→J/ψϕ and B0d→J/ψK*0 of B mesons produced in pp collisions at √s=7  TeV are used to determine the ratio of fragmentation fractions fs/fd. From the observed B0s→J/ψϕ and B0d→J/ψK*0 yields, the quantity (fs/fd)[B(B0s→J/ψϕ)/B(B 0d→J/ψK*0)] is measured to be 0.199±0.004(stat)±0.008(syst). Using a recent theory prediction for [B(B0s→J/ψϕ)/B(B0d→J/ψK*0)] yields (fs/fd)=0.240±0.004(stat)±0.010(syst)±0.017(th). This result is based on a new approach that provides a significant improvement of the world average

Addressing the 'forgotten art of fundoscopy': evaluation of a novel teaching ophthalmoscope

Background: Direct ophthalmoscopy is an essential skill that students struggle to learn. A novel 'teaching ophthalmoscope' has been developed that allows a third person to observe the user's view of the fundus. Objectives: To evaluate the potential use of this device as an aid to learning, and as a tool for objective assessment of competence. Methods: Participants were randomised to be taught fundoscopy either with a conventional direct ophthalmoscope (control) or with the teaching device (intervention). Following this teaching session, participant competence was assessed within two separate objective structured clinical examination (OSCE) stations: the first with the conventional ophthalmoscope and the second with the teaching device. Each station was marked by two independent masked examiners. Students were also asked to rate their own confidence in fundoscopy on a scale of 1-10. Scores of competence and confidence were compared between groups. The agreement between examiners was used as a marker for inter-rater reliability and compared between the two OSCE stations. Results: Fifty-five medical students participated. The intervention group scored significantly better than controls on station 2 (19.8 vs 17.6; P=0.01). They reported significantly greater levels of confidence in fundoscopy (7.3 vs 4.9; P<0.001). Independent examiner scores showed significantly improved agreement when using the teaching device during assessment of competence, compared to the conventional ophthalmoscope (r=0.90 vs 0.67; P<0.001). Conclusion: The teaching ophthalmoscope is associated with improved confidence and objective measures of competence, when compared with a conventional direct ophthalmoscope. Used to assess competence, the device offers greater reliability than the current standard