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Introduction: The mobilization and ambulation of patients with severe cardiogenic shock supported with peripheral veno-arterial extracorporeal membrane oxygenation (pVA-ECMO) and concomitant femoral intra-aortic balloon pump (IABP) support is not well-described. This technical paper describes an ambulation protocol to prevent deconditioning in this critically ill patient population., Methods: A protocol for the ambulation of patients with pVA-ECMO and concomitant IABP support was created in December 2022 and implemented at a single center. To initiate ambulation, patients were initially placed in a vertical position utilizing the VitalGo Total Lift Bed (VitalGo Systems, Miramar, FL) with mechanical circulatory support device monitoring performed by a critical care multidisciplinary team. Retrospective analysis of successfully ambulated patients was performed from December 2022 to January 2024., Results: A total of 35 patients out of 112 patients with ECMO support were ambulated in the study period. Four of these patients had pVA-ECMO with concomitant IABP support with this cohort completing a total of 11 sessions during the study period. Patients ambulated an average of 200 feet per session without any adverse events, including cannula and balloon pump migration or displacement. Three of the four patients studied were either bridged to an advanced therapy including orthotopic heart transplant or durable left ventricular assist device or were discharged., Conclusion: A protocol for ambulation of CS patients with pVA-ECMO support and concomitant femoral IABP support is feasible and can safely be implemented in this critically ill patient population. Further multicenter studies are necessary to determine the overall impact of ambulation on patient outcomes., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Careful filtering is necessary for observations of quantum phenomena in superconducting circuits at low temperatures. Measurements of coherence between quantum states require extensive filtering to protect against noise coupled from room temperature electronics. We demonstrate distributed transmission line filters which cut off exponentially at GHz frequencies and can be anchored at the base temperature of a dilution refrigerator. The compact design makes them suitable to filter many different bias lines in the same setup, necessary for the control and measurement of superconducting qubits.

We report on the effect of the backaction of a single Cooper pair transistor electrometer (E) on the charge state of a superconducting box (B). The charge is e periodic in the gate bias of B when E is operated near voltages 2 Delta/e or 4 Delta/e. We show that this is due to quasiparticle poisoning of B at a rate proportional to the number of quasiparticle tunneling events in E per second. We are able to eliminate this backaction and recover 2e-charge periodicity using a new measurement method based on switching-current modulation of E.

We report the observation of the universal distribution of transparencies, predicted by Schep and Bauer [Phys. Rev. Lett. 78, 3015 (1997)] for dirty sharp interfaces, in uniform Nb/AlO(x)/Nb junctions with high specific conductance (10(8) ohm(-1) cm(-2)). Experiments used the BCS density of states in superconducting niobium for transparency distribution probing. Experimental results for both the dc I-V curves at magnetic-field-suppressed supercurrent and the Josephson critical current in zero magnetic field coincide remarkably well with calculations based on the multimode theory of multiple Andreev reflections and the Schep-Bauer distribution.

In 1935, Schrodinger attempted to demonstrate the limitations of quantum mechanics using a thought experiment in which a cat is put in a quantum superposition of alive and dead states. The idea remained an academic curiosity until the 1980s when it was proposed that, under suitable conditions, a macroscopic object with many microscopic degrees of freedom could behave quantum mechanically, provided that it was sufficiently decoupled from its environment. Although much progress has been made in demonstrating the macroscopic quantum behaviour of various systems such as superconductors, nanoscale magnets, laser-cooled trapped ions, photons in a microwave cavity and C60 molecules, there has been no experimental demonstration of a quantum superposition of truly macroscopically distinct states. Here we present experimental evidence that a superconducting quantum interference device (SQUID) can be put into a superposition of two magnetic-flux states: one corresponding to a few microamperes of current flowing clockwise, the other corresponding to the same amount of current flowing anticlockwise.

We present evidence for transitions between fluxoid wells of a SQUID due to cascaded, two-photon processes. Such transitions are evidenced by an anomalous dependence on the transition rate from the one-photon resonant level within the initial well, which cannot be explained by previously observed macroscopic resonant tunneling. These two-photon processes may be a significant source of decoherence in SQUID qubits subject to microwave radiation.