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Caloric curve for mononuclear configurations

The caloric curve for mononuclear configurations is studied with a schematic model. We investigate the dependence of the entropy on the density and effective-mass profiles. In finite nuclei, a plateau in the caloric curve is a consequence of decreasing density and the destruction of correlations rather than an indication of phase coexistence. The mononuclear regime is metastable with respect to binary fission at low excitation energy and with respect to multifragmentation at high excitation. The statistical framework presented here is suitable to treat scenarios where experimental conditions are set to favor a population of highly excited mononuclei.     

Spin echo MRI in the evaluation of hearts with a double outlet right ventricle: usefulness and limitations

The surgical approach to a double outlet right ventricle (DORV) is dependent on the spatial relationship of the semilunar valves, outflow tracts and ventricular septal defect (VSD). The purpose of the study was to assess the value of MRI for the evaluation of cardiovascular anatomy in patients before and after surgery for DORV. Spin echo MRI was performed in 12 patients with DORV (eight preoperative and four postoperative patients). Thin-section MRI was performed in three orthogonal planes and selected angulated views were obtained. Conventional imaging by color Doppler echocardiography and cine-angiocardiography and surgical findings, when present, served as the reference standards. The results found that the spatial relationship between semilunar valves and VSD was accurately assessed by MRI in eight out of eight preoperative patients. In the four postoperative cases MRI depicted the morphology of both outflow tracts and provided adequate information on their patency. Of the eight preoperative patients, five have undergone corrective surgery and the MRI findings were confirmed. MRI provided additional information to conventional imaging preoperatively in three cases in which the VSD opened into the outlet portion of the DORV, without there being a direct relation to a semilunar valve. In two preoperative cases in which the VSD was directly committed to the aorta, conventional imaging was conclusive. MRI was unable to depict aberrant chordae tendineae in four out of four cases. We conclude that MRI provides accurate additional anatomic information in patients with DORV, which is helpful in presurgical planning as well as during follow-up. Spin echo MRI does not visualize aberrant chordae tendineae.     

Tidal effects and the proximity decay of nuclei

We examine the decay of the 3.03 MeV state of (8)Be evaporated from an excited projectilelike fragment following a peripheral heavy-ion collision. The relative energy of the daughter alpha particles exhibits a dependence on the decay angle of the (8)Be(*), indicative of a tidal effect. A comparison of the measured tidal effect with a model suggests a measurable nuclear proximity interaction.     

Unifying pricing formula for several stochastic volatility models with jumps

In this paper, we introduce a unifying approach to option pricing under continuous‐time stochastic volatility models with jumps. For European style options, a new semi‐closed pricing formula is derived using the generalized complex Fourier transform of the corresponding partial integro‐differential equation. This approach is successfully applied to models with different volatility diffusion and jump processes. We also discuss how to price options with different payoff functions in a similar way. In particular, we focus on a log‐normal and a log‐uniform jump diffusion stochastic volatility model, originally introduced by Bates and Yan and Hanson, respectively. The comparison of existing and newly proposed option pricing formulas with respect to time efficiency and precision is discussed. We also derive a representation of an option price under a new approximative fractional jump diffusion model that differs from the aforementioned models, especially for the out‐of‐the money contracts. Copyright © 2017 John Wiley & Sons, Ltd.