The flux qubit revisited to enhance coherence and reproducibility.

The scalable application of quantum information science will stand on reproducible and controllable high-coherence quantum bits (qubits). Here, we revisit the design and fabrication of the superconducting flux qubit, achieving a planar device with broad-frequency tunability, strong anharmonicity, high reproducibility and relaxation times in excess of 40 μs at its flux-insensitive point. Qubit relaxation times T across 22 qubits are consistently matched with a single model involving resonator loss, ohmic charge noise and 1/f-flux noise, a noise source previously considered primarily in the context of dephasing.

Thermal and Residual Excited-State Population in a 3D Transmon Qubit.

Remarkable advancements in coherence and control fidelity have been achieved in recent years with cryogenic solid-state qubits. Nonetheless, thermalizing such devices to their milliKelvin environments has remained a long-standing fundamental and technical challenge. In this context, we present a systematic study of the first-excited-state population in a 3D transmon superconducting qubit mounted in a dilution refrigerator with a variable temperature.

Coherence and decay of higher energy levels of a superconducting transmon qubit.

We present measurements of coherence and successive decay dynamics of higher energy levels of a superconducting transmon qubit. By applying consecutive π pulses for each sequential transition frequency, we excite the qubit from the ground state up to its fourth excited level and characterize the decay and coherence of each state. We find the decay to proceed mainly sequentially, with relaxation times in excess of 20  μs for all transitions.

Prothrombin fragment 1+2 in urine as a marker on coagulation activity in patients with suspected pulmonary embolism.

Introduction: We have recently reported that increased levels of urine prothrombin fragment 1+2 reflected radiologically verified deep vein thrombosis. In this study we evaluated whether urine prothrombin fragment 1+2 was associated with pulmonary embolism in non-selected patients.

Materials And Methods: Patients with clinical suspected pulmonary embolism were interviewed on comorbidities and medications.

Clinical venous thromboembolism following joint surgery: effect of extended thromboprophylaxis on its annual frequency and postoperative pattern over 22 years.

We describe annual incidences and 6-month postoperative patterns of clinical venous thromboembolism (VTE) in 9078 patients undergoing major joint surgery in a Scandinavian hospital. In cohort I (1989-1999), low-molecular-weight heparin thromboprophylaxis for 7 to 10 days was uniformly introduced, 5-week thromboprophylaxis becoming routine after total hip replacement (THR), partially applied after hip fracture surgery (HFS), but not used after total knee replacement (TKR) thereafter (2003-2011; cohort II). Mean annual VTE incidence was lower in cohort II than in cohort I after THR and HFS but not after TKR.

Thrombin split products (prothrombin fragment 1 + 2) in urine in patients with suspected deep vein thrombosis admitted for radiological verification.

Introduction: The appearance of prothrombin fragment 1 + 2 (F1 + 2) in urine has been associated with postoperative hypercoagulability and thromboembolism. We wanted to assess if F1 + 2 was released in urine (uF1 + 2) in patients with procoagulant disorders, and if higher levels were found in patients with radiological verified deep vein thrombosis (DVT).

Materials And Methods: Consecutive patients were interviewed on comorbidities and medications.

Current-induced switching of perpendicularly magnetized magnetic layers using spin torque from the spin Hall effect.

We show that in a perpendicularly magnetized Pt/Co bilayer the spin-Hall effect (SHE) in Pt can produce a spin torque strong enough to efficiently rotate and switch the Co magnetization. We calculate the phase diagram of switching driven by this torque, finding quantitative agreement with experiments. When optimized, the SHE torque can enable memory and logic devices with similar critical currents and improved reliability compared to conventional spin-torque switching.

Fractures of the fifth metacarpal.

Background: The literature is limited concerning the epidemiological issues of fracture in the fifth metacarpal bone.

Purpose: To explore the incidence and types of this fracture, and how the fracture is related to age, gender, trauma mechanism, and at what day of the week the causing trauma occurred.

Material And Methods: All hand fractures registered at the Department of Radiology, Buskerud Hospital, Norway, in the period between 2004 and 2006 were reviewed.

Shift in imaging modalities of the urinary tract over a 25-year period and its impact on ionizing radiation doses given to patients.

Objectives: To explore the shift in imaging modalities used when examining the urinary tract over the period 1979-2003 and to see how this shift, together with a radiation protection policy, have influenced the doses of ionizing radiation used.

Material And Methods: Activity reports from a department of radiology were reviewed. Relevant radiation dose estimates were obtained from the Norwegian Radiation Protection Authority.

Shift in imaging modalities of gastrointestinal tract through 25 years and its impact on patient ionizing radiation doses.

We wanted to explore the shift in modalities when diagnosing the gastrointestinal tract through the last three decades and see how this has influenced on the radiation doses given to this patient population. Activity reports from a central hospital in the years of 1979-2003 have been reviewed. The x-ray based modalities have decreased, while there has been a marked increase in colonoscopies, gastroscopies, ultrasound, and magnetic resonance cholangiopancreatography.

Shift in imaging modalities of the spine through 25 years and its impact on patient ionizing radiation doses.

Study Design: Retrospective.

Objective: To explore the shift in modalities when diagnosing the spine in the years 1979-2003. To see how this shift, together with a radiation protective policy, have influenced on the ionizing radiation doses.

Frequency and timing of clinical venous thromboembolism after major joint surgery.

Over a 13-year period we studied all patients who underwent major hip and knee surgery and were diagnosed with objectively confirmed symptomatic venous thromboembolism, either deep venous thrombosis or non-fatal pulmonary embolism, within six months after surgery. Low-molecular-weight heparin had been given while the patients were in hospital. There were 5607 patients.

Acute osteomyelitis as a complication of varicella.

Varicella is a common viral infection in childhood, and acute osteomyelitis is one of the rare but serious complications. We report two cases of osteomyelitis as a complication of varicella. The possibilities and limitations of the different imaging modalities are discussed, as well as imaging findings during the course of this condition.

Risk of clinical pulmonary embolism after joint surgery in patients receiving low-molecular-weight heparin prophylaxis in hospital: a 10-year prospective register of 3,954 patients.

We studied the incidence of nonfatal, radiologically-confirmed, clinical pulmonary embolism (PE) after major joint surgery during 10 years of observation. The findings are based on a prospective register of all patients undergoing total hip replacement (THR), total knee replacement (TKR), or nailed hip fracture (NHF) in a Scandinavian hospital between 1989 and 1998. All patients received thromboprophylaxis with low-molecular-weight heparin, continued until discharge.

Late occurring clinical deep vein thrombosis in joint-operated patients.

In a prospective study of 4,840 patients, we determined the annual incidence of clinical deep vein thrombosis (DVT) in mobilized, discharged orthopedic-operated "high-risk" patients (hip replacement surgery, knee replacement surgery, nailed hip fracture) and assumed "low-risk" patients (diagnostic knee arthroscopy). In addition, the time from the operation to the time when the patients were readmitted with clinically suspected DVT and the distribution of radiologically-confirmed DVT were recorded. Thromboprophylaxis was routinely given for about 10 days to the high-risk groups during the hospital stay but not to patients undergoing knee arthroscopy.

[Osteomyelitis as a complication of varicella].

Osteomyelitis is a rare complication after varicella. It should, however, be considered in any child who develops pain in a limb during or after a varicella infection. An 18 month old boy with a five day history of varicella infection was hospitalized.

Three dimensional CT evaluation of occipito-atlanto-axial dislocation in rheumatoid arthritis.

Involvement of the upper cervical spine, with possible instability and dislocation of the atlanto-axial-cervico-occipital joints in patients with rheumatoid arthritis (RA), is routinely monitored with conventional radiographs. As disease progresses severe interpretation problems occur, especially when looking for cranial migration of the odontoid process. The aim of the present study was to evaluate whether three dimensional CT examination should be considered for such monitoring.

[Krukenberg tumor. A seldom considered condition?].

In 1896, Krukenberg described what he presumed was a new type of primary ovarian neoplasm. The true metastatic nature of this lesion was established six years later. Some 10% of all ovarian malignant lesions are regarded as metastatic.

[Abnormality as differential diagnosis in atlas fracture].

In some patients, suspected fractures of the cranial part of the cervical spine are difficult to diagnose properly without the use of computed tomography or MT. In addition to imaging and positioning problems, the possibility of anomalies of the atlas vertebra may complicate the diagnostic considerations. Proper knowledge of such anomalies may facilitate the diagnostic procedures.

Autosomal dominant osteopetrosis: report of a Norwegian family with radiographic or anamnestic findings differing from the generally accepted classification.

Objective: Autosomal dominant osteopetrosis is currently divided into two, possibly three subgroups. The present study of a Norwegian family, however, suggests that such a grouping is not generally valid.

Patients And Methods: A Norwegian family has been studied over four generations.

Imaging routines for the esophagus, small bowel, abdomen, and liver in six Norwegian hospitals from 1975 to 1993.

The roles of liver scintigraphy in addition to other imaging modalities of the esophagus and the small bowel and the use of abdominal flat films were studied in six Norwegian hospitals between 1975 and 1993. Parallel to the introduction of ultrasonography, the use of liver scintigraphy disappeared almost completely. Barium studies of the esophagus, to some degree, have been replaced by endoscopy, whereas use of barium studies of the small bowel remained unchanged or increased.

[Arteriovenous fistula as a complication of percutaneous renal biopsy].

Arteriovenous fistulae is a well known but rarely diagnosed complication of percutaneous biopsy of kidney allografts. In most cases the fistula are clinically occult. Most of the remaining fistulas disappear spontaneously.

Changes in radiological routines following the introduction of computed tomography. A retrospective study from two Norwegian hospitals.

Diagnostic imaging routines have changed rapidly during the last two decades. The real revolution started with the introduction of computed tomography into routine clinical work in the middle of the 1970s. Simultaneously, a tremendous sophistication of ultrasonography took place, and shortly later, magnetic resonance imaging started its "career.

Changes in diagnostic imaging routines of the stomach and the large bowel during the period between 1975 and 1992.

In a retrospective study on diagnostic imaging of the stomach and large bowel, we evaluated the examination routines in six Norwegian hospitals for the period between 1975 and 1992. For both organ systems, a shift in routines from radiological examination toward endoscopy was observed. For the stomach there was a significant correlation between an increase in the use of endoscopy and a decrease in the use of X-ray examinations.