The emerging quantum technological applications call for fast and accurate initialization of the corresponding devices to low-entropy quantum states. To this end, we theoretically study a recently demonstrated quantumcircuit refrigerator in the case of nonlinear quantum electric circuits such as superconducting qubits. The maximum refrigeration rate of transmon and flux qubits is observed to be roughly an order of magnitude higher than that of usual linear resonators, increasing flexibility in the design. We find that for typical experimental parameters, the refrigerator is suitable for resetting different qubit types to fidelities above 99.99% in a few or a few tens of nanoseconds depending on the scenario. Thus the refrigerator appears to be a promising tool for quantum technology and for detailed studies of open quantum systems.

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Purpose To report the 5-year results of a prospective trial of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation in the prone position (P-APBI). Methods Post-menopausal patients with Stage I breast cancer with non palpable <2 cm tumors, negative margins, and negative nodes, positive hormonal receptors, and no extensive intraductal component (EIC) were eligible. The trial was offered only once eligible patients had refused to undergo standard whole-breast radiotherapy. Patients were simulated and treated on a dedicated table for prone set-up. The 3D-CRT delivered was 30 Gy in five 6 Gy/daily fractions over 10 days with port film verification at each treatment. Ipsilateral breast, ipsilateral nodal, contralateral breast, and distant failure (IBF, INF, CBF, DF) were estimated using the cumulative incidence method. Disease-free, overall, and cancer-specific survival (DFS, OS, CSS) were recorded. Results One hundred patients accrued to this IRB- approved prospective trial, one with bilateral breast cancer. One patient withdrew consent after simulation and another elected to interrupt radiotherapy after receiving two treatments. Ninety-eight patients are evaluable for toxicity and, in one case, both breasts were treated with PBI. Median patient age was 68 years (range 53–88 years); in 55% the tumor size was <1 cm. All patients had hormonal receptor positive cancers: 87% underwent adjuvant anti-hormonal therapy. At a median follow-up of 64 months (range, 2–125 months), there was one local recurrence (1% IBF) and one contralateral breast cancer (1% CBF). There were no deaths due to breast cancer by 5 years. Grade 3 late toxicities occurred in 2 patients (1 breast edema, 1 transient breast pain). Cosmesis was rated good/excellent in 89% of patients with at least 36 months follow-up. Conclusions Five-year efficacy and toxicity of 3D-CRT to deliver prone-PBI are comparable to other experiences with similar follow-up.

BackgroundVentricular septal defects are the commonest congenital cardiac malformations. They can exist in isolation, but are also found as integral components of other cardiac anomalies, such as tetralogy of Fallot, double outlet right ventricle, or common arterial trunk. As yet, there is no agreement on how best to classify such defects, nor even on the curved surface that is taken to represent the defect.MethodsBased on our previous pathological and clinical experiences, we have reviewed the history of classification of holes between the ventricles. We proposed that the defects are best defined as representing the area of deficient ventricular septation. This then permits the recognition of clinically significant variants according to the anatomic borders, and the way the curved surface representing the area of deficient septation opens into the morphologically right ventricle.ResultsClinical manifestation depends on the size of the defect, and on the relationship between systemic and pulmonary vascular resistances. Symptoms include failure to thrive, along with the manifestations of the increase in flow of blood to the lungs. Diagnosis can be made by physical examination, but is confirmed by echocardiographic interrogation, which delineates the precise anatomy, and also provides the physiologic information required for optimal clinical decision-making. Cardiac catheterization offers additional information regarding hemodynamics, particularly if there is a concern regarding an increase in pulmonary vascular resistance. Hemodynamic assessment is rarely necessary to make decisions regarding management, although it can be helpful if assessing symptomatic adults with hemodynamically restrictive defects. In infants with defects producing large shunts, surgical closure is now recommended in most instances as soon as symptoms manifest. Only in rare cases is palliative banding of the pulmonary trunk now recommended. Closure with devices inserted on catheters is now the preferred approach for many patients with muscular defects, often using a hybrid procedure. Therapeutic closure should now be anticipated with virtually zero mortality, and with excellent anticipated long-term survival.ConclusionVentricular septal defects are best defined as representing the borders of the area of deficient ventricular septation. An approach on this basis permits recognition of the clinically significant phenotypic variants.