UBV stellar photometry of bright stars in GC M5. I. UV colour-magnitude and colour-colour diagrams and some peculiarities in the HB stellar distribution

We present stellar photometry in the UBV passbands for the globular cluster M5 = NGC5904. The observations, short-exposured photographic plates and CCD frames, were obtained in the RC-focus of the 2m telescope of the Natl. Astron. Obs. 'Rozhen'. All stars in an annulus with radius 1 < r < 5.5 arcmin were measured. We show that the UV CMDs describe different evolutionary stages in a better manner than the 'classical' (V, B-V) diagram. We use HB stars, with known spectroscopic Teff, to check the validity of the colour zero-point. A review of all known UV-bright star candidates in M5 is made and some of their parameters are catalogued. Six new stars of this kind are suspected on the basis of their position on the CMD. New assessment of the cluster reddening and metallicity is done using the (U-B, B-V) diagram. We find [Fe/H]= -1.38, which confirms the Zinn & West (1984) value contrasting with recent spectroscopic estimates. In an effort to clarify the question of the gap in the BHB stellar distribution and to investigate some other peculiarities, we use the relatively long-base colour index U-V. A comparison of the unreddened (V, U-V) distribution of HB stars with a canonical ZAHB model (Dorman et al. 1993) reveals that the hottest stars rise above the model line. We find this similar to the 'u-jump' found in the Stroemgren photometry (Grundahl et al. 1998, 1999). (U-B)o indeces of 18 BHB stars with (B-V)o in [-0.02, 0.18] were used to estimate their ultraviolet deficiency. It is shown that low gravity log g < 2 Kurucz's atmospheric models fit well the observed distribution of these stars along the two-colour diagram.Comment: 9 pages, 7 EPS figures. MNRAS accepte

Prevalence of Age-Related Macular Degeneration in Europe: The Past and the Future

Purpose Age-related macular degeneration (AMD) is a frequent, complex disorder in elderly of European ancestry. Risk profiles and treatment options have changed considerably over the years, which may have affected disease prevalence and outcome. We determined the prevalence of early and late AMD in Europe from 1990 to 2013 using the European Eye Epidemiology (E3) consortium, and made projections for the future. Design Meta-analysis of prevalence data. Participants A total of 42 080 individuals 40 years of age and older participating in 14 population-based cohorts from 10 countries in Europe. Methods AMD was diagnosed based on fundus photographs using the Rotterdam Classification. Prevalence of early and late AMD was calculated using random-effects meta-analysis stratified for age, birth cohort, gender, geographic region, and time period of the study. Best-corrected visual acuity (BCVA) was compared between late AMD subtypes; geographic atrophy (GA) and choroidal neovascularization (CNV). Main Outcome Measures Prevalence of early and late AMD, BCVA, and number of AMD cases. Results Prevalence of early AMD increased from 3.5% (95% confidence interval [CI] 2.1%–5.0%) in those aged 55–59 years to 17.6% (95%

How should we optimize cardiac resynchronization therapy?

Optimization of cardiac resynchronization therapy is increasingly performed. Numerous methods have been proposed, many being echocardiographic. Both the technique and the timing of optimization are contentious. Whether acute haemodynamic benefits translate into long-term improvements in remodelling, symptoms, or prognosis is unknown. Recent guidelines from the American Society of Echocardiography advocate routine optimization. Here, we objectively review the principles, methods, timing, and evidence supporting optimization. Despite limited validation, optimization was included in landmark clinical trials and is inherent in evidence-based practice. Randomized controlled trials comparing methods are needed, with long-term clinical endpoints. For now, optimization should be performed using the iterative method, according to the CARE-HF protocol

Limited clinical utility of CT coronary angiography in a district hospital setting

Background: Studies have demonstrated considerable accuracy of multi-slice CT coronary angiography (MSCT-CA) in comparison to invasive coronary angiography (I-CA) for evaluating coronary artery disease (CAD). The extent to which published MSCT-CA accuracy parameters are transferable to routine practice beyond high-volume tertiary centres is unknown. Aim: To determine the accuracy of MSCT-CA for the detection of CAD in a Scottish district general hospital. Design: Prospective study of diagnostic accuracy. Method: One hundred patients with suspected CAD recruited from two Glasgow hospitals underwent both MSCT-CA (Philips Brilliance 40 × 0.625 collimation, 50–200 ms temporal resolution) and I-CA. Studies were reported by independent, blinded radiologists and cardiologists and compared using the AHA 15-segment model. Results: Of 100 patients [55 male, 45 female, mean (SD) age 58.0 (10.7) years], 59 and 41% had low-intermediate and high pre-test probabilities of significant CAD, respectively. Mean (SD) heart rate during MSCT-CA was 68.8 (9.0) bpm. Fifty-seven per cent of patients had coronary artery calcification and 35% were obese. Patient prevalence of CAD was 38%. Per-patient sensitivity, specificity, positive and negative (NPV) predictive values for MSCT-CA were 92.1, 47.5, 52.2 and 90.6%, respectively. NPV was reduced to 75.0% in the high pre-test probability group. Specificity was compromised in patients with sub-optimally controlled heart rates, calcified arteries and elevated BMI. Conclusion: Forty-Slice MSCT-CA has a high NPV for ruling out significant CAD when performed in a district hospital setting in patients with low-intermediate pre-test probability and minimal arterial calcification. Specificity is compromised by clinically appropriate strategies for dealing with unevaluable studies. Effective heart rate control during MSCT-CA is imperative. National guidelines should be utilized to govern patient selection and direct MSCT-CA reporter training to ensure quality control