12 research outputs found
Epistaxis as the initial presentation in a case of rheumatic heart disease
Rheumatic heart disease (RHD) remains prevalent in developing nations and shows varied presentations, causing diagnostic challenge. Here, we report a case of RHD in a 13-year-old boy who presented with recurrent epistaxis as the initial symptom. On detailed work-up, echocardiography revealed the incidental finding of involvement of mitral and aortic valves but the patient never had any symptom as per the diagnostic criteria for RHD. This report highlights the clinical and epidemiological significance of atypical presentations as such cases might go undiagnosed and untreated, seeking medical attention in advanced stages, which would have otherwise contributed to the actual prevalence of the disease in the population
Reanalysis of the Gas-cooled fast reactor experiments at the zero power facility Proteus â Spectral indices
PROTEUS is a zero power reactor at the Paul Scherrer Institute which has been employed during the 1970âs to study experimentally the physics of the gas-cooled fast reactor. Reaction rate distributions, flux spectrum and reactivity effects have been measured in several configurations featuring PuO2/UO2 fuel, absorbers, large iron shields, and thorium oxide and thorium metal fuel either distributed quasihomogeneously in the reference PuO2/UO2 lattice or introduced in the form of radial and axial blanket zones. This papers focus on the spectral indices â including fission and capture in 232Th and 237Np - measured in the reference PuO2/UO2 lattices and their predictions with an MCNPX model specially developed for the PROTEUS-GCFR core. Predictions were obtained with JEFF-3.1 and -3.11, ENDF/B-VII.0 and VII.1, and JENDL-3.3 and -4.0. A general good agreement was demonstrated. The ratio of 232Th fission to 239Pu fission, however, was under-predicted by 8.7±2.1% and 6.5±2.1% using ENDF/B-VII.0 and VII.1, respectively. Finally, the capture rates in 237Np tended to be underpredicted by the JEFF and JENDL libraries, although the new cross section in JEFF-3.1.1 slightly improved the 237Np capture to 239Pu fission results (3.4±2.4%)
Dynamics of long-term electricity demand profile: Insights from the analysis of Swiss energy systems
System Dynamics Simulation to Explore the Impact of Low European Electricity Prices on Swiss Generation Capacity Investments
European electricity markets are coping with low energy prices as a result of overinvestments in generation capacity, subsidies for renewables and the financial crisis of 2008. In this chapter we explore the implications of low electricity prices on the Swiss electricity market, which is facing the additional challenge of phasing out nuclear power plants and market liberalization. System Dynamics is utilized to model and simulate the long-term impacts on investments in new generation capacity, security of supply and future electricity prices. Simulation results indicate that the current low electricity prices are likely to persist for another decade. The most likely response to the low prices is an underinvestment in generation capacity, with the risk of scarcity pricing under low security of supply, as it coincides with the decommissioning of nuclear power plants. There is little evidence this will lead to boom-and-bust investment cycles. Finally, in the long-term we observe a shift towards renewable energy sources and natural gas fired power plants, resulting in more volatile electricity prices. These findings are similar to earlier studies of the liberalized German and Belgian electricity markets, which are also facing the challenges of a nuclear phase-out under depressed European prices