High efficiency, high frequency magnetic deflection driver

Electromagnetic deflection yoke stores energy during the scan and releases it in the flyback or retrace. The operation of the device involves a method of switching to a voltage high enough to dissipate the flyback pulse during the retrace time and then operating during the scan time at a much lower voltage

The feasibility study for electronic imaging system with the photoheliograph

The development of the electronic subsystems used for the photoheliograph and its application for a high resolution study of the sun are discussed. Basic considerations are as follows: (1) determination of characteristics of solar activity within the spectral response of the photoheliograph, (2) determination of the space vehicles capable of carrying the photoheliograph, (3) analysis of the capability of the ground based data gathering network to assimilate the generated information, and (4) the characteristics of the photoheliograph and the associated spectral filters

Origin of the n-type conductivity of InN: the role of positively charged dislocations

As-grown InN is known to exhibit high unintentional n-type conductivity. Hall measurements from a range of high-quality single-crystalline epitaxially grown InN films reveal a dramatic reduction in the electron density (from low 1019 to low 1017 cm–3) with increasing film thickness (from 50 to 12 000 nm). The combination of background donors from impurities and the extreme electron accumulation at InN surfaces is shown to be insufficient to reproduce the measured film thickness dependence of the free-electron density. When positively charged nitrogen vacancies (VN+) along dislocations are also included, agreement is obtained between the calculated and experimental thickness dependence of the free-electron concentration

Optimally robust shortcuts to population inversion in two-level quantum systems

We examine the stability versus different types of perturbations of recently proposed shortcuts-to-adiabaticity to speed up the population inversion of a two-level quantum system. We find optimally robust processes using invariant based engineering of the Hamiltonian. Amplitude noise and systematic errors require different optimal protocols.Comment: 17 pages, 7 figure

Conduit choice for coronary artery bypass grafting after mediastinal radiation

ObjectivePatients who have undergone prior mediastinal radiation might require coronary artery bypass grafting. However, there is some concern regarding potential radiation damage to the internal thoracic artery. Our objective was to assess the late patency of the internal thoracic artery and venous grafts in patients with prior mediastinal radiation.MethodsPatients undergoing coronary artery bypass grafting at our clinic after prior mediastinal radiation were identified, and medical records, including operative reports, clinical notes, and coronary angiography, were reviewed.ResultsBetween 1985 and 2005, 138 patients had coronary artery bypass grafting after mediastinal radiation. Of these, 25 underwent clinically indicated postoperative angiography. The mean patient age was 56.1 ± 13.8 years, and 24% were female. All patients received between 3000 and 6000 rads in fractionated doses. Seventy-two percent of patients had 3-vessel coronary artery disease. At late angiography (mean, 2.2 years), 6 (32%) of 19 internal thoracic arteries and 13 (27%) of 48 venous or radial arterial conduits showed stenosis of 70% or greater (P = .72). Assessing only grafts that were anastomosed to the left anterior descending coronary artery, 35% (6 of 17) of internal thoracic artery grafts and 60% (3 of 5) of non–internal thoracic artery grafts showed narrowing of 70% or greater (P = .61). Among patients who received a graft to the left anterior descending coronary artery (n = 113), however, age-adjusted survival at 5 years was superior among those receiving an internal thoracic artery graft to the left anterior descending coronary artery.ConclusionsInternal thoracic artery graft patency among patients with prior radiation was less than expected and similar to that for venous grafts, although the effect of conduit disease versus distal target vessel runoff is unknown. Despite this, late survival was superior among those receiving an internal thoracic artery graft to the left anterior descending coronary artery. These data support use of an internal thoracic artery graft to the left anterior descending coronary artery when it appears grossly to be an acceptable conduit

Transition from electron accumulation to depletion at InGaN surfaces

The composition dependence of the Fermi-level pinning at the oxidized (0001) surfaces of n-type InxGa1−xN films (0<=x<=1) is investigated using x-ray photoemission spectroscopy. The surface Fermi-level position varies from high above the conduction band minimum (CBM) at InN surfaces to significantly below the CBM at GaN surfaces, with the transition from electron accumulation to depletion occurring at approximately x=0.3. The results are consistent with the composition dependence of the band edges with respect to the charge neutrality level

Surface electronic properties of undoped InAlN alloys

The variation in surface electronic properties of undoped c-plane InxAl1−xN alloys has been investigated across the composition range using a combination of high-resolution x-ray photoemission spectroscopy and single-field Hall effect measurements. For the In-rich alloys, electron accumulation layers, accompanied by a downward band bending, are present at the surface, with a decrease to approximately flatband conditions with increasing Al composition. However, for the Al-rich alloys, the undoped samples were found to be insulating with approximate midgap pinning of the surface Fermi level observed

Radiography of a normal fault system by 64,000 high-precision earthquake locations: The 2009 L'Aquila (central Italy) case study

We studied the anatomy of the fault system where the 2009 L'Aquila earthquake (M_W 6.1) nucleated by means of ~64 k high-precision earthquake locations spanning 1 year. Data were analyzed by combining an automatic picking procedure for P and S waves, together with cross-correlation and double-difference location methods reaching a completeness magnitude for the catalogue equal to 0.7 including 425 clusters of similar earthquakes. The fault system is composed by two major faults: the high-angle L'Aquila fault and the listric Campotosto fault, both located in the first 10 km of the upper crust. We detect an extraordinary degree of detail in the anatomy of the single fault segments resembling the degree of complexity observed by field geologists on fault outcrops. We observe multiple antithetic and synthetic fault segments tens of meters long in both the hanging wall and footwall along with bends and cross fault intersections along the main fault and fault splays. The width of the L'Aquila fault zone varies along strike from 0.3 km where the fault exhibits the simplest geometry and experienced peaks in the slip distribution, up to 1.5 km at the fault tips with an increase in the geometrical complexity. These characteristics, similar to damage zone properties of natural faults, underline the key role of aftershocks in fault growth and co-seismic rupture propagation processes. Additionally, we interpret the persistent nucleation of similar events at the seismicity cutoff depth as the presence of a rheological (i.e., creeping) discontinuity explaining how normal faults detach at depth

Radiography of a normal fault system by 64,000 high-precision earthquake locations: The 2009 L’Aquila (central Italy) case study

We studied the anatomy of the fault system where the 2009 L’Aquila earthquake (MW 6.1) nucleated by means of ~64 k high-precision earthquake locations spanning 1 year. Data were analyzed by combining an automatic picking procedure for P and S waves, together with cross-correlation and double-difference location methods reaching a completeness magnitude for the catalogue equal to 0.7 including 425 clusters of similar earthquakes. The fault system is composed by two major faults: the high-angle L’Aquila fault and the listric Campotosto fault, both located in the first 10 km of the upper crust. We detect an extraordinary degree of detail in the anatomy of the single fault segments resembling the degree of complexity observed by field geologists on fault outcrops. We observe multiple antithetic and synthetic fault segments tens of meters long in both the hanging wall and footwall along with bends and cross fault intersections along the main fault and fault splays. The width of the L’Aquila fault zone varies along strike from 0.3 km where the fault exhibits the simplest geometry and experienced peaks in the slip distribution, up to 1.5 km at the fault tips with an increase in the geometrical complexity. These characteristics, similar to damage zone properties of natural faults, underline the key role of aftershocks in fault growth and co-seismic rupture propagation processes. Additionally, we interpret the persistent nucleation of similar events at the seismicity cutoff depth as the presence of a rheological (i.e., creeping) discontinuity explaining how normal faults detach at depth