Impressive late stent recoil of a drug-eluting resorbable magnesium coronary stent

n/

Coherent excitation transport through ring-shaped networks

The coherent quantum transport of matter wave through a ring-shaped circuit attached to leads defines an iconic system in mesoscopic physics that has allowed both to explore fundamental questions in quantum science and to draw important avenues for conceiving devices of practical use. Here we study the source-to-drain transport of excitations going through a ring-network, without propagation of matter waves. We model the circuit in terms of a spin system with specific long-range interactions that are relevant for quantum technology, such as Rydberg atoms trapped in optical tweezers or ion traps. Inspired by the logic of rf- and dc-SQUIDs, we consider rings with one and two local energy offsets, or detunings. As a combination of specific phase shifts in going though the localized detunings and as a result of coherent tunneling, we demonstrate how the transport of excitations can be controlled, with a distinctive dependence on the range of interactions.Comment: Main text: 9 pages, 4 figures. Appendix: 16 pages, 10 figure

Influence of Tension Stiffening on the Flexural Stiffness of Reinforced Concrete Circular Sections

Within this paper, the assessment of tension stiffening effects on a reinforced concrete element with the circular sections subjected to axial and bending loads is presented. To this purpose, an enhancement of an analytical model already present within the actual technical literature is proposed. The accuracy of the enhanced method is assessed by comparing the experimental results carried out in past research and the numerical ones obtained by the model. Finally, a parametric study is executed in order to study the influence of axial compressive force on the flexural stiffness of reinforced concrete elements that are characterized by a circular section, comparing the secant stiffness evaluated at yielding and at maximum resistance, considering and not considering the effects of tension stiffness

Controlled flow of excitations in a ring-shaped network of Rydberg atoms

Highly excited Rydberg atoms are a powerful platform for quantum simulation and information processing. Here, we propose atomic ring networks to study chiral currents of Rydberg excitations. The currents are controlled by a phase pattern imprinted via a Raman scheme and can persist even in the presence of dephasing. Depending on the interplay between the Rabi coupling of Rydberg states and the dipole-dipole atom interaction, the current shows markedly different features. The excitations propagate with a velocity displaying a characteristic peak in time, reflecting the chiral nature of the current. We find that the time-averaged current in a quench behaves similarly to the ground-state current. This analysis paves the way for the development of new methods to transport information in atomic networks.Comment: 6 pages main, 6 figures + appendice

Statistical mechanics of the Cluster-Ising model

We study a Hamiltonian system describing a three-spin-1/2 cluster-like interaction competing with an Ising-like anti-ferromagnetic interaction. We compute free energy, spin correlation functions and entanglement both in the ground and in thermal states. The model undergoes a quantum phase transition between an Ising phase with a nonvanishing magnetization and a cluster phase characterized by a string order. Any two-spin entanglement is found to vanish in both quantum phases because of a nontrivial correlation pattern. Neverthless, the residual multipartite entanglement is maximal in the cluster phase and dependent on the magnetization in the Ising phase. We study the block entropy at the critical point and calculate the central charge of the system, showing that the criticality of the system is beyond the Ising universality class.Comment: To be published in Physical Review

Chern-Simons theory and BCS superconductivity

We study the relationship between the holomorphic unitary connection of Chern-Simons theory with temporal Wilson lines and the Richardson's exact solution of the reduced BCS Hamiltonian. We derive the integrals of motion of the BCS model, their eigenvalues and eigenvectors as a limiting case of the Chern-Simons theory.Comment: 23 page

Quantum many particle systems in ring-shaped optical lattices

In the present work we demonstrate how to realize 1d-optical closed lattice experimentally, including a {\it tunable} boundary phase-twist. The latter may induce ``persistent currents'', visible by studing the atoms' momentum distribution. We show how important phenomena in 1d-physics can be studied by physical realization of systems of trapped atoms in ring-shaped optical lattices. A mixture of bosonic and/or fermionic atoms can be loaded into the lattice, realizing a generic quantum system of many interacting particles.Comment: 10 pages, 5 figures. To be published in PR

Spin wave contribution to entanglement in Heisenberg models

Employing the Holstein?Primakoff transformation, we obtain an approximate description of both the ground state entanglement and the entanglement dynamics in a spin system in terms of spin waves. As an example, we apply the method to a two-dimensional spin system

Malignancy as a risk factor in single-stage combined approach for simultaneous elective surgical diseases

AbstractObjectiveTo identify morbidity and mortality risk factors in patients with synchronous diseases who underwent single-stage combined (SSC) surgery.MethodsWe considered data of 328 patients, each with multiple, elective, synchronous surgical problems treated by a SSC operation. By univariate and multivariate analysis we evaluated many patient-, disease - or treatment-related variables with respect to post-operative mortality, morbidity, and hospital stay.ResultsTwo combined procedures were synchronously performed in 283 patients (86%), 3 combined procedures in 45 patients (14%). Post-operative mortality and morbidity rates were 3% and 24%, respectively, and median duration of hospital stay was 9 days. The occurrence of a surgical oncology procedure emerged as the most important independent risk factor for post-operative mortality and morbidity.ConclusionsThe safety of SSC surgery for the treatment of synchronous problems appears similar to that of multi-stage procedures. The understanding of risk factors for this surgical approach could be useful in order to improve patient selection

Multimodal validation of facial expression detection software for real-­time monitoring of affect in patients with suicidal intent

We sought to test the hypothesis that previously validated biomarkers of high risk for suicide, namely EEG event related potentials (ERP), Galvanic skin response (GSR) and heart rate variability (HRV) can be employed in combination with facial affect and pupil dilation measures, in a novel diagnostic battery that will ultimately increase reliability of clinical evaluations of suicidal persons