Resonant Raman scattering off neutral quantum dots

Resonant inelastic (Raman) light scattering off neutral GaAs quantum dots which contain a mean number, N=42, of electron-hole pairs is computed. We find Raman amplitudes corresponding to strongly collective final states (charge-density excitations) of similar magnitude as the amplitudes related to weakly collective or single-particle excitations. As a function of the incident laser frequency or the magnetic field, they are rapidly varying amplitudes. It is argued that strong Raman peaks should come out in the spin-density channels, not related to valence-band mixing effects in the intermediate states.Comment: Accepted in Physical Review

Combining to innovate: A collaborative interprofessional learning approach to delivering Tobacco Use Prevention and Cessation (TUPAC) education for undergraduate oral health students

This paper provides a description of a pilot project in Tobacco Use Prevention and Cessation (TUPAC) in response to a national and international trend to include TUPAC curriculum components in the clinical education of undergraduate oral health students. In order to deliver quality brief intervention strategies for smokers a need to adequately prepare oral health students was identified during student clinical placements. An interprofessional (IP) project team was established with membership from the University of Adelaide’s School of Dentistry, QuitSA, Cancer Council SA, the South Australian Dental Service (SADS) Somerton Park and TAFESA’s Faculty of Dental Studies to streamline the efficient use of resources and most importantly draw on a diverse range of interprofessional health care expertise. On the website for The UK Centre for the Advancement of Interprofessional Education (CAIPE) (2002) it states that “Interprofessional education occurs when two or more professions learn from and about each other to improve collaboration and the quality of care”. Through interprofessional learning (IPL) in classroom and clinical settings, second year Bachelor and Advanced Diploma oral health students were provided with the opportunity to develop an understanding of the respective roles of each health professional responsible for delivering positive health initiatives in the area of TUPAC. With limited national oral health curricula in the area of TUPAC, the project team forged links with the University of Manitoba’s Dental Hygiene Program, and the convenor of the TUPAC in Dental and Dental Hygiene Undergraduate Education European Workshops for curriculum benchmarking against evidence based criteria. Most importantly as the IP concept of health care considers the patient at the centre of the health care team, assessment was designed to encourage a patient centred approach through the review and analysis of a clinical case study. A formal evaluation of this project is currently in progress, however results were not yet available at the time of publication

Spin polarization and magneto-luminescence of confined electron-hole systems

A BCS-like variational wave-function, which is exact in the infinite field limit, is used to study the interplay among Zeeman energies, lateral confinement and particle correlations induced by the Coulomb interactions in strongly pumped neutral quantum dots. Band mixing effects are partially incorporated by means of field-dependent masses and g-factors. The spin polarization and the magneto-luminescence are computed as functions of the number of electron-hole pairs present in the dot and the applied magnetic field.Comment: To appear in Phys. Rev.

Patients who choose not to dialyze: a prospective national observational study in Australia.

BACKGROUND: It is unclear how many incident patients with stage 5 chronic kidney disease (CKD) referred to nephrologists are presented with information about conservative care as a treatment option and how many plan not to dialyze. STUDY DESIGN: National observational survey study with random-effects logistic regression. SETTING & PARTICIPANTS: Incident adult and pediatric pre-emptive transplant, dialysis, and conservative-care patients from public and private renal units in Australia, July to September 2009. PREDICTORS: Age, sex, health insurance status, language, time known to nephrologist, timing of information, presence of caregiver, unit conservative care pathway, and size of unit. OUTCOMES & MEASUREMENTS: The 2 main outcome measures were information provision to incident patients about conservative care and initial treatment regardless of planned conservative care. RESULTS: 66 of 73 renal units (90%) participated. 10 (15%) had a formal conservative-care pathway. Of 721 incident patients with stage 5 CKD, 470 (65%) were presented with conservative care as a treatment option and 102 (14%) planned not to dialyze; median age was 80 years. Multivariate analysis for information provision showed that patients older than 65 years (OR, 3.40; 95% CI, 1.97-5.87) and those known to a nephrologist for more than 3 months (OR, 6.50; 95% CI, 3.18-13.30) were more likely to receive information about conservative care. Patients with conservative care as planned initial treatment were more likely to be older than 65 years (OR, 4.71; 95% CI, 1.77-12.49) and women (OR, 2.23; 95% CI, 1.23-4.02) than those who started dialysis therapy. Those with private health insurance were less likely to forgo dialysis therapy (OR, 0.40; 95% CI, 0.17-0.98). LIMITATIONS: Cross-sectional design prohibited longer term outcome measurement. Excluded patients with stage 5 CKD managed in the community. CONCLUSIONS: 1 in 7 patients with stage 5 CKD referred to nephrologists plans not to dialyze. Comprehensive service provision with integrated palliative care needs to be improved to meet the demands of the aging population

Patients who choose not to dialyze: a prospective national observational study in Australia.

BACKGROUND: It is unclear how many incident patients with stage 5 chronic kidney disease (CKD) referred to nephrologists are presented with information about conservative care as a treatment option and how many plan not to dialyze. STUDY DESIGN: National observational survey study with random-effects logistic regression. SETTING & PARTICIPANTS: Incident adult and pediatric pre-emptive transplant, dialysis, and conservative-care patients from public and private renal units in Australia, July to September 2009. PREDICTORS: Age, sex, health insurance status, language, time known to nephrologist, timing of information, presence of caregiver, unit conservative care pathway, and size of unit. OUTCOMES & MEASUREMENTS: The 2 main outcome measures were information provision to incident patients about conservative care and initial treatment regardless of planned conservative care. RESULTS: 66 of 73 renal units (90%) participated. 10 (15%) had a formal conservative-care pathway. Of 721 incident patients with stage 5 CKD, 470 (65%) were presented with conservative care as a treatment option and 102 (14%) planned not to dialyze; median age was 80 years. Multivariate analysis for information provision showed that patients older than 65 years (OR, 3.40; 95% CI, 1.97-5.87) and those known to a nephrologist for more than 3 months (OR, 6.50; 95% CI, 3.18-13.30) were more likely to receive information about conservative care. Patients with conservative care as planned initial treatment were more likely to be older than 65 years (OR, 4.71; 95% CI, 1.77-12.49) and women (OR, 2.23; 95% CI, 1.23-4.02) than those who started dialysis therapy. Those with private health insurance were less likely to forgo dialysis therapy (OR, 0.40; 95% CI, 0.17-0.98). LIMITATIONS: Cross-sectional design prohibited longer term outcome measurement. Excluded patients with stage 5 CKD managed in the community. CONCLUSIONS: 1 in 7 patients with stage 5 CKD referred to nephrologists plans not to dialyze. Comprehensive service provision with integrated palliative care needs to be improved to meet the demands of the aging population

The views of patients and carers in treatment decision making for chronic kidney disease: systematic review and thematic synthesis of qualitative studies

Objective To synthesise the views of patients and carers in decision making regarding treatment for chronic kidney disease, and to determine which factors influence those decisions

Magnetic field dependence of the energy of negatively charged excitons in semiconductor quantum wells

A variational calculation of the spin-singlet and spin-triplet state of a negatively charged exciton (trion) confined to a single quantum well and in the presence of a perpendicular magnetic field is presented. We calculated the probability density and the pair correlation function of the singlet and triplet trion states. The dependence of the energy levels and of the binding energy on the well width and on the magnetic field strength was investigated. We compared our results with the available experimental data on GaAs/AlGaAs quantum wells and find that in the low magnetic field region (B<18 T) the observed transition are those of the singlet and the dark triplet trion (with angular momentum $L_z=-1$), while for high magnetic fields (B>25 T) the dark trion becomes optically inactive and possibly a transition to a bright triplet trion (angular momentum $L_z=0$) state is observed.Comment: 9 pages, 10 figures submitted to Phys. Rev.

The COMPTEL instrumental line background

The instrumental line background of the Compton telescope COMPTEL onboard the Compton Gamma-Ray Observatory is due to the activation and/or decay of many isotopes. The major components of this background can be attributed to eight individual isotopes, namely 2D, 22Na, 24Na, 28Al, 40K, 52Mn, 57Ni, and 208Tl. The identification of instrumental lines with specific isotopes is based on the line energies as well as on the variation of the event rate with time, cosmic-ray intensity, and deposited radiation dose during passages through the South-Atlantic Anomaly. The characteristic variation of the event rate due to a specific isotope depends on its life-time, orbital parameters such as the altitude of the satellite above Earth, and the solar cycle. A detailed understanding of the background contributions from instrumental lines is crucial at MeV energies for measuring the cosmic diffuse gamma-ray background and for observing gamma-ray line emission in the interstellar medium or from supernovae and their remnants. Procedures to determine the event rate from each background isotope are described, and their average activity in spacecraft materials over the first seven years of the mission is estimated.Comment: accepted for publication in A&A, 22 pages, 21 figure