Entangled States Induced by Electron-Phonon Interaction in Two-Dimensional Materials.

We report on the effects of electron-phonon interaction in materials such as graphene, showing that it enables the formation of a gap bridged by unique edge states. These states exhibit a distinctive locking among propagation direction, valley, and phonon mode, allowing for the generation of electron-phonon entangled states whose parts can be easily split. We discuss the effect of the chiral atomic motion in the zone boundary phonons leading to this effect. Our findings shed light on how to harness these unconventional states in quantum research.

A dynamical model for Brownian molecular motors driven by inelastic electron tunneling.

In recent years, several artificial molecular motors driven and controlled by electric currents have been proposed. Similar to Brownian machines, these systems work by turning random inelastic tunneling events into a directional rotation of the molecule. Despite their importance as the ultimate component of future molecular machines, their modeling has not been sufficiently studied. Here, we develop a dynamical model to describe these systems. We illustrate the validity and usefulness of our model by applying it to a well-known molecular motor, showing that the obtained results are consistent with the available experimental data. Moreover, we demonstrate how to use our model to extract some difficult-to-access microscopic parameters. Finally, we include an analysis of the expected effects of current-induced forces (CIFs). Our analysis suggests that, although nonconservative contributions of the CIFs can be important in some scenarios, they do not seem important in the analyzed case. Despite this, the conservative contributions of CIFs could be strong enough to significantly alter the system's dynamics.

Copropagating Edge States Produced by the Interaction between Electrons and Chiral Phonons in Two-Dimensional Materials.

Unlike the chirality of electrons, the intrinsic chirality of phonons has only surfaced in recent years. Here, we report on the effects of the interaction between electrons and chiral phonons in two-dimensional materials by using a nonperturbative solution. We show that chiral phonons introduce inelastic Umklapp processes resulting in copropagating edge states that coexist with a continuum. Transport simulations further reveal the robustness of the edge states. Our results hint on the possibility of having a metal embedded with hybrid electron-phonon states of matter.

Guía basada en la evidencia para el manejo perioperatorio de la anticoagulación oral con warfarina en pacientes con alto riesgo embólico que serán llevados a implante de dispositivos de estimulación cardiaca / Evidence-based guidelines for the perioperative management of oral anticoagulation with warfarin in patients scheduled for implantation of a cardiac electronic device

Introducción: El manejo perioperatorio de la anticoagulación crónica representa dificultad para los médicos que realizan implantes de dispositivos de estimulación cardíaca, quienes utilizan la terapia puente con heparinas con la intención de disminuir el riesgo de sangrado. Sin embargo, este tratamiento es controversial. Objetivo: Generar recomendaciones basadas en evidencia sobre el tratamiento perioperatorio de la anticoagulación de los pacientes con riesgo embólico moderado y alto, que requieren anticoagulación oral con warfarina y serán llevados a implante de dispositivos de estimulación cardíaca. Métodos: Se realizó una búsqueda de la literatura para identificar guías de práctica clínica basadas en evidencia, las cuales se calificaron con la herramienta AGREE II. Se actualizó la evidencia desde el 1 de enero de 2009 hasta el 30 de noviembre de 2013, incluidas revisiones sistemáticas y experimentos clínicos. Los estudios se calificaron con los instrumentos GRADE y SIGN. Se generaron recomendaciones con metodología GRADE, llevadas a consenso formal de expertos. Resultados: Las guías SIGN y CHEST tuvieron la mejor calificación con AGREE II. Con la nueva evidencia disponible proveniente de tres revisiones sistemáticas y dos experimentos clínicos, se generó recomendación fuerte a favor de continuar la anticoagulación oral con warfarina durante el perioperatorio de implante de dispositivos de estimulación cardíaca en pacientes con riesgo embólico moderado y alto. Conclusiones: A partir de la nueva evidencia cambia la recomendación propuesta por las guías SIGN y CHEST. La alternativa de continuar la terapia con warfarina a cambio de realizar terapia puente, debe considerarse en la práctica clínica.

Introduction: The perioperative management of chronic anticoagulation concerns all physicians involved in the implantation of cardiac electronic devices (either pacemakers and cardioverter-defibrillators). Switching from warfarin to low molecular weight heparins (LMWH) has been performed to reduce the risk of bleeding. However, this approach has been shown to be controversial. Objective: To generate evidence-based recommendations on the perioperative management of oral anticoagulation with warfarin in patients who will undergo the implantation of a cardiac electronic device. Methods: A literature search was performed to identify evidence-based clinical practice guidelines, which were assessed using the AGREE II instrument. The guidelines were updated with systematic reviews and randomized clinical trials published from February 2009 to November 2013 comparing the continuation of warfarin versus switching to a LMWH or withholding warfarin. These studies were analyzed using the SIGN and GRADE scales to assess methodological quality. Recommendations were put forward through an expert panel. Results: The guidelines with highest methodological quality were the SIGN (Scottish Intercollegiate Guidelines Network) guideline published in June 2013 and the CHEST guideline published in February 2012. The update included three systematic reviews and two randomized clinical trials. The continuation of warfarin for the perioperative management of implantable cardiac electronic devices in patients with moderate and high risk is recommended. Conclusion: Based on the new evidence changes the recommendation given by the CHEST SIGN and guides. The alternative of continued therapy with warfarin in exchange for performing therapy bridge, should be considered in clinical practice.

Semiclassical theory of time-reversal focusing.

Time-reversal mirrors have been successfully implemented for various kinds of waves propagating in complex media. In particular, acoustic waves in chaotic cavities exhibit a refocalization that is extremely robust against external perturbations or the partial use of the available information. We develop a semiclassical approach in order to quantitatively describe the refocusing signal resulting from an initially localized wave packet. The time-dependent reconstructed signal grows linearly with the temporal window of injection, in agreement with the acoustic experiments, and reaches the same spatial extension of the original wave packet. We explain the crucial role played by the chaotic dynamics for the reconstruction of the signal and its stability against external perturbations.