Selective Production of Rydberg-Stark States of Positronium

Rydberg positronium (Ps) atoms have been prepared in selected Stark states via two-step (1s→2p→nd/ns) optical excitation. Two methods have been used to achieve Stark-state selection: a field ionization filter that transmits the outermost states with positive Stark shifts, and state-selected photoexcitation in a strong electric field. The former is demonstrated for n=17 and 18 while the latter is performed for n=11 in a homogeneous electric field of 1.9  kV/cm. The observed spectral intensities and their dependence on the polarization of the laser radiation are in agreement with calculations that include the perturbations of the intermediate n=2 manifold. Our results pave the way for the generation of Rydberg Ps atoms with large electric dipole moments that are required for the realization of schemes to control their motion using inhomogeneous electric fields, an essential feature of some proposed Ps free-fall measurements requiring focused beams of long-lived atoms

Preliminary evidence supports circulating microRNAs as prognostic biomarkers for type 2 diabetes.

Background:Circulating microRNAs are emerging as potential prognostic biomarkers for the development of type 2 diabetes. However, microRNAs are also associated with complications from impaired glucose metabolism (e.g. endothelial cell function). Prior studies have not evaluated for associations between trajectories of circulating microRNAs with trajectories of fasting blood glucose over time and the responses to behavioral interventions to reduce risk. This study performed longitudinal assessment of microRNAs and fasting blood glucose and identified relationships between microRNAs and behavioral risk reduction interventions. Methods:MicroRNAs (n = 353) were measured in subsets (n = 10, n = 8) of participants from previously completed clinical trials that studied behavioral risk reduction interventions. Fasting blood glucose trajectories were associated with changes in 45 microRNAs over 12 months. Results:Following a 3-month physical activity and dietary intervention compared with baseline, 13 microRNAs were differentially expressed. Seven microRNAs (i.e. miR-106b, miR-20b, miR-363, miR-486, miR-532, miR-92a and miR-93) were commonly identified between the two analyses. Conclusions:Further studies are needed to determine which microRNAs are prognostic biomarkers of risk for type 2 diabetes versus consequences of impaired glucose metabolism. Additional future directions of this research are to differentiate whether microRNAs are prognostic and/or diagnostic biomarkers for risk for type 2 diabetes and predictive biomarkers of responses to risk reduction interventions

Outdoor music festivals: Cacophonous consumption or melodious moderation?

Large outdoor music festivals have emerged as part of a general expansion of licensed recreational activities, but in research terms they have been largely impenetrable due to commercial sensitivities. These sensitivities notwithstanding, the number and scale of such events necessitate a greater understanding of alcohol and drug use and the potential to promote normative protective behaviours in this context. This study examines self-reported alcohol and drug behaviours of 1589 attendees at a music festival in Scotland during the summer of 2008. Similarities between the outdoor rock music festivals and the dance club scene are considered alongside the challenges associated with risk reduction in these settings. Results show that alcohol was consumed by the majority of samples; however, negative consequences were reported by a minority of respondents, suggesting evidence of controlled hedonism within a situation traditionally associated with unrestrained excess. Similarly, the majority of samples did not use drugs. The majority also report a number of self-regulating protective behaviours suggesting that alcohol and drug use is contained within a developing social culture of ‘controlled intoxication’. Results further suggest that although music festivals are transitory events, there is a degree of consistency amongst attendees. Music festivals may therefore be atypical but potentially effective environments to increase protective behaviours using normative messaging and modern communications media. This study was resourced exclusively by local alcohol and drug partnerships

Single-shot positron annihilation lifetime spectroscopy with LYSO scintillators

We have evaluated the application of a lutetium yttrium oxyorthosilicate (LYSO) based detector to single-shot positron annihilation lifetime spectroscopy. We compare this detector directly with a similarly configured PbWO4 scintillator, which is the usual choice for such measurements. We find that the signal to noise ratio obtained using LYSO is around three times higher than that obtained using PbWO4 for measurements of Ps excited to longer-lived (Rydberg) levels, or when they are ionized soon after production. This is due to the much higher light output for LYSO (75% and 1% of NaI for LYSO and PbWO4 respectively). We conclude that LYSO is an ideal scintillator for single-shot measurements of positronium production and excitation performed using a low-intensity pulsed positron beam

Effect on cardiovascular disease risk factors of interventions to alter consultations between practitioners and patients with type 2 diabetes: A systematic review and meta-analysis of trials in primary care

$\textbf{Objective:}$ To examine the effect on cardiovascular (CVD) risk factors of interventions to alter consultations between practitioners and patients with type 2 diabetes. $\textbf{Search Strategy:}$ Electronic and manual citation searching to identify relevant randomized controlled trials (RCTs). $\textbf{Inclusion Criteria:}$ RCTs that compared usual care to interventions to alter consultations between practitioners and patients. The population was adults aged over 18 years with type 2 diabetes. Trials were set in primary care. $\textbf{Data extraction and synthesis:}$ We recorded if explicit theory-based interventions were used, how consultations were measured to determine whether interventions had an effect on these and calculated weighted mean differences for CVD risk factors including glycated haemoglobin (HbA$_{1c}$), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), LDL cholesterol (LDL-C) and HDL cholesterol (HDL-C). $\textbf{Results:}$ We included seven RCTs with a total of 2277 patients with type 2 diabetes. A range of measures of the consultation was reported, and underlying theory to explain intervention processes was generally undeveloped and poorly applied. There were no overall effects on CVD risk factors; however, trials were heterogeneous. Subgroup analysis suggested some benefit among studies in which interventions demonstrated impact on consultations; statistically significant reductions in HbA$_{1c}$ levels (weighted mean difference, −0.53%; 95% CI: [−0.77, −0.28]; $P$<.0001; $I^{2}$ =46%). $\textbf{Conclusions:}$ Evidence of effect on CVD risk factors from interventions to alter consultations between practitioners and patients with type 2 diabetes was heterogeneous and inconclusive. This could be explained by variable impact of interventions on consultations. More research is required that includes robust measures of the consultations and better development of theory to elucidate mechanisms.HDM was an Academic Clinical Fellow, Andrew Cooper is funded by the University of Cambridge MRC Epidemiology Unit (grant code: MC_UU_12015/4), SJG is an NIHR Senior Investigator. The primary care unit is a member of the National Institute for Health Research (NIHR) School for Primary Care Research and supported by NIHR Research funds. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health

Electrostatically Guided Rydberg Positronium

We report experiments in which positronium (Ps) atoms were guided using inhomogeneous electric fields. Ps atoms in Rydberg-Stark states with principal quantum number n=10 and electric dipole moments up to 610 D were prepared via two-color two-photon optical excitation in the presence of a 670  V cm−1 electric field. The Ps atoms were created at the entrance of a 0.4 m long electrostatic quadrupole guide, and were detected at the end of the guide via annihilation gamma radiation. When the lasers were tuned to excite low-field-seeking Stark states, a fivefold increase in the number of atoms reaching the end of the guide was observed, whereas no signal was detected when high-field-seeking states were produced. The data are consistent with the calculated geometrical guide acceptance