Fluctuations of Energy-Relaxation Times in Superconducting Qubits

Superconducting qubits are an attractive platform for quantum computing since they have demonstrated high-fidelity quantum gates and extensibility to modest system sizes. Nonetheless, an outstanding challenge is stabilizing their energy-relaxation times, which can fluctuate unpredictably in frequency and time. Here, we use qubits as spectral and temporal probes of individual two-level-system defects to provide direct evidence that they are responsible for the largest fluctuations. This research lays the foundation for stabilizing qubit performance through calibration, design, and fabrication.

Is a nurse consultant impact toolkit relevant and transferrable to the radiography profession? An evaluation project

INTRODUCTION

Consultant posts were developed to strengthen strategic leadership whilst maintaining front line service responsibilities and clinical expertise. The nursing profession has attempted to develop tools to enable individuals to evaluate their own practice and consider relevant measurable outcomes. This study evaluated the feasibility of transferring such a nursing 'toolkit' to another health profession.

METHOD

This evaluation was structured around a one-day workshop where a nurse consultant impact toolkit was appraised and tested within the context of consultant radiographic practice. The adapted toolkit was subsequently validated using a larger sample at a national meeting of consultant radiographers.

RESULTS

There was broad agreement that the tools could be adopted for use by radiographers although several themes emerged in relation to perceived gaps within the nursing template, confirming the initial exercise. This resulted in amendments to the original scope and a proposed new evaluation tool.

CONCLUSION

The impact toolkit could help assess individual and collaborat ive role impact at a local and national level. The framework provides consultant radiographers with an opportunity to understand and highlight the contribution their roles have on patients, staff, their organisation and the wider profession.

Spectroscopic signatures of localization with interacting photons in superconducting qubits

Quantized eigenenergies and their associated wave functions provide extensive information for predicting the physics of quantum many-body systems. Using a chain of nine superconducting qubits, we implement a technique for resolving the energy levels of interacting photons. We benchmark this method by capturing the main features of the intricate energy spectrum predicted for two-dimensional electrons in a magnetic field-the Hofstadter butterfly. We introduce disorder to study the statistics of the energy levels of the system as it undergoes the transition from a thermalized to a localized phase. Our work introduces a many-body spectroscopy technique to study quantum phases of matter.

Trends in breast reconstruction practices in a specialized breast tertiary referral centre

BACKGROUND

Breast reconstruction is an important component of multidisciplinary breast cancer management. The practice of breast reconstruction after mastectomy has evolved significantly in the past decade as a result of both increasing mastectomy rates and advances in reconstructive strategy. These changes have significantly influenced the contemporary surgical management of breast cancer. The aim of this study was to examine trends in breast reconstruction after mastectomy in an Irish population.

METHODS

Data were reviewed from a database of all patients who had mastectomy with or without breast reconstruction at Galway University Hospital, a tertiary breast cancer referral centre, between 2004 and 2014. Trends in breast reconstruction after mastectomy were explored with respect to patient demographics, clinicopathological features, and neoadjuvant and adjuvant therapy.

RESULTS

Of 1303 patients who underwent mastectomy during interval studied, 706 (54.2 per cent) had breast reconstruction after mastectomy. In 629 patients (89·1 per cent), breast reconstruction was performed in the immediate setting. Reconstruction rates increased over time from 20·5 per cent in 2004 to 44·7 per cent in 2014. Reconstruction was more commonly performed in younger patients and those with benign, in situ and early-stage disease. A negative relationship between radiotherapy and reconstruction was observed. A pedicled flap with or without an implant was the most commonly used reconstructive approach in patients receiving radiotherapy.

CONCLUSION

Breast reconstruction after mastectomy has become the standard of care in the surgical treatment of breast cancer. Recent trends show a transition favouring implant-based approaches.

Proliferative myositis of the latissimus dorsi presenting in a 20-year-old male athlete

We describe the case of a 20-year-old rower presenting with an uncommon condition of Proliferative Myositis (PM) affecting the Latissimus Dorsi (LD). PM is a rare, benign tumour infrequently developing in the upper back. Its rapid growth and firm consistency may mistake it for sarcoma at presentation. Therefore, careful multidisciplinary work-up is crucial, and should involve appropriate radiological and histopathological investigations. Here, we propose the aetiology of LD PM to be persistent myotrauma induced by repetitive rowing motions. Symptoms and rate of progression ultimately determine the management which includes surveillance and/or conservative resection. There have been no documented cases of recurrence or malignant transformation.

Targeted next-generation sequencing identifies clinically relevant mutations in patients with chronic neutrophilic leukemia at diagnosis and blast crisis

PURPOSE

Chronic neutrophilic leukemia is a rare form of myeloproliferative neoplasm characterized by mature neutrophil hyperleukocytosis. The majority of patients harbor somatic mutations of CSF3R gene and are potentially amenable to targeted therapy with JAK inhibitors. The incidence and clinical significance of additional mutations requires clarification.

MATERIALS AND METHODS

A next-generation sequencing approach for myeloid malignancy-associated mutations was applied to diagnostic and matched blast crisis samples from four chronic neutrophilic leukemia patients.

RESULTS

Next-generation sequencing confirmed the CSF3R T618I in all patients with identification of concurrent SRSF2, SETBP1, NRAS and CBL mutations at diagnosis. At blast crisis, clonal evolution was evidenced by an increased CSF3R T618I allele frequency and by loss or acquisition of CBL and NRAS mutations.

CONCLUSION

The diagnostic utility of a targeted next-generation sequencing approach was clearly demonstrated with the identification of additional mutations providing the potential for therapeutic stratification of chronic neutrophilic leukemia patients.

Observation of Classical-Quantum Crossover of 1/f Flux Noise and Its Paramagnetic Temperature Dependence

By analyzing the dissipative dynamics of a tunable gap flux qubit, we extract both sides of its two-sided environmental flux noise spectral density over a range of frequencies around 2k_{B}T/h≈1  GHz, allowing for the observation of a classical-quantum crossover. Below the crossover point, the symmetric noise component follows a 1/f power law that matches the magnitude of the 1/f noise near 1 Hz. The antisymmetric component displays a 1/T dependence below 100 mK, providing dynamical evidence for a paramagnetic environment. Extrapolating the two-sided spectrum predicts the linewidth and reorganization energy of incoherent resonant tunneling between flux qubit wells.