Freestyle aortic root prosthesis in combination with aortic replacement and open anastomosis: a retrospective analysis.

Background: The Freestyle® bioprosthesis is used for pathologies of the aortic root. Additional resection of the ascending aorta and the proximal arch in dissections or aneurysms might be indicated. The aim was to assess mid-term outcome regarding prosthetic performance, stroke, reoperations, and survival in various pathologies comparing patients with and without additional procedures on the ascending aorta and proximal arch focusing on the standardised technique of unilateral antegrade cerebral perfusion under moderate hypothermia.

On the Quantumness of Multiparameter Estimation Problems for Qubit Systems.

The estimation of more than one parameter in quantum mechanics is a fundamental problem with relevant practical applications. In fact, the ultimate limits in the achievable estimation precision are ultimately linked with the non-commutativity of different observables, a peculiar property of quantum mechanics. We here consider several estimation problems for qubit systems and evaluate the corresponding R, a measure that has been recently introduced in order to quantify how incompatible the parameters to be estimated are.

Noisy Quantum Metrology Enhanced by Continuous Nondemolition Measurement.

We show that continuous quantum nondemolition (QND) measurement of an atomic ensemble is able to improve the precision of frequency estimation even in the presence of independent dephasing acting on each atom. We numerically simulate the dynamics of an ensemble with up to N=150 atoms initially prepared in a (classical) spin coherent state, and we show that, thanks to the spin squeezing dynamically generated by the measurement, the information obtainable from the continuous photocurrent scales superclassically with respect to the number of atoms N. We provide evidence that such superclassical scaling holds for different values of dephasing and monitoring efficiency.

Nightside condensation of iron in an ultrahot giant exoplanet.

Ultrahot giant exoplanets receive thousands of times Earth's insolation. Their high-temperature atmospheres (greater than 2,000 kelvin) are ideal laboratories for studying extreme planetary climates and chemistry. Daysides are predicted to be cloud-free, dominated by atomic species and much hotter than nightsides.

Measuring the Kinetics of Neutral Pair Evaporation from Cluster Ions of Ionic Liquid in the Drift Region of a Differential Mobility Analyzer.

Singly charged clusters [CA]C or [CA]A of two salts [CA] are produced by electrospray ionization of alcohol solutions of the ionic liquids 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate (EMI-FAP) and 1,2-dimethyl-3-propylimidazolium-methide (DMPI-Me). The rate of neutral pair evaporation into [CA] + [CA]C or [CA]A is studied in atmospheric pressure as a function of temperature for the positive trimer ion ( = 2) of DMPI-Me and the negative trimer ion of EMI-FAP. The trimer is separated from all other electrosprayed ions in a first differential mobility analyzer (DMA) and then transferred through a cooled tube to a second DMA whose drift gas is kept at a controlled temperature (25 °C < < 100 °C).