A case of congenital tricuspid regurgitation associated with atrial septal defect and peripheral pulmonary stenosis

This report describes a 5-year-old girl with congenital tricuspid regurgitation associated with an atrial septal defect and peripheral pulmonary stenosis. The girl was diagnosed with the heart murmur at birth and recently developed the cardiomegaly. Cardiac echocardiography and catheterization showed severe tricuspid regurgitation, an atrial septal defect of the secundum type and peripheral pulmonary stenosis. In the operative findings, the tricuspid annulus was dilated to 33 mm in diameter, and leaflets were attached normally to the antomic annulus. There was a large cleft of the anterior leaflet of the tricuspid valve. Suture of the cleft and annuloplasty of the tricuspid valve, suture closure of the atrial septal defect and patch dilatation of peripheral pulmonary stenosis were successfully performed. Including this case, 19 other cases with congenital tricuspid regurgitation undergoing surgery were reported to date.     

Electrophysiological elucidation of pathways of intrinsic horizontal connections in rat visual cortex

In single pass perfused rat liver, rapid osmotic water shifts across the plasma membrane in response to hyperosmolar urea were followed by monitoring liver mass and transient concentrating or diluting effects on Na+ concentration in effluent perfusate. Sudden addition or removal of hyperosmolar urea (200mM, resulting in a step change of the perfusate osmolarity from 305 to 505 mosmol/l) had little effect on liver mass or Na+ activity in the effluent perfusate, suggesting that urea equilibrated at a rate similar to that of water across the liver plasma membrane. When, however, phloretin (0.2mM) was present, sudden addition (removal) of urea (200mM) induced within seconds a marked and transient decrease (increase) of both liver mass and effluent Na+ concentration, suggestive of transient osmotic water shifts out of/into the cells. Although to a lesser extent, comparable effects were induced when urea was added/removed in the presence of the phloretin-related phenol compounds 2,4,6-trihydroxyacetophenone (5mM) and 2,4,5-trihydroxybutyrophenone (5mM). Phloretin-induced inhibition of urea export from livers preloaded with [14C]urea was reversible, and no saturation of urea transport was found at concentrations up to 200mM. In contrast to [14C]urea transport, [3H]water transport across the plasma membrane was not affected by phloretin. The data indicate that urea export across the hepatocyte plasma membrane is almost as fast as water export. The urea transport mechanism is sensitive to phloretin and other phenol compounds, works with high capacity and is distinct from the water-transporting system. The regulation of this putative transport mechanism and its relevance for hepatic nitrogen metabolism remain to be established.     

LEICA: a low energy ion composition analyzer for the study of solarand magnetospheric heavy ions

The SAMPEX (Solar, Anomalous, and Magnetospheric Particle Explorer) LEICA instrument is designed to measure ~0.5-5-MeV/nucleon solar and magnetospheric ions over the range from He-Ni. The instrument is a time-of-flight (TOF) mass spectrometer, which measures particle TOF over an ~0.5-m path and the residual energy deposited in an array of Si solid state detectors. Large-area microchannel plates are used, resulting in a large geometrical factor for the instrument (0.6 cm² sr), which is essential for accurate compositional measurements in small solar flares and in studies of precipitating magnetospheric heavy ions     

Thermal stability of interfaces between metals and InP-based materials

The thermal stability of interfaces between metals (Ni, Pt, Ti, Mo) and III-V compound semiconductors has been investigated by the application of Rutherford backscattering spectrometry. Metal diffusion and interfacial lattice disorder of the semiconductors were analyzed for various metal/semiconductor samples annealed at temperatures up to 500°C. The interfaces of Ni/GaAs and Ti/GaAs were found to be more stable than those of Ni/In-based semiconductors and Ti/ In-based semiconductors, respectively. Faster diffusion of Pt atoms was ob-served in In-and As-containing materials than in P-containing materials. Mo/ semiconductor interfaces were the most stable.     

Development of a distributed sensing technique using Brillouinscattering

This paper reviews the developments of a distributed strain and temperature sensing technique that uses Brillouin scattering in single-mode optical fibers. This technique is based on strain- and temperature-induced changes in the Brillouin frequency shift. Several approaches for measuring the weak Brillouin line are compared     

Analysis and design-optimization of LCC resonant inverter forhigh-frequency AC distributed power system

The analysis and design of an LCC resonant inverter for a 20 kHz AC distributed power system are presented. Several resonant converter topologies are assessed to determine their suitability for high efficiency power conversion, under resistive and reactive loads. Two LCC-resonant inverter designs were implemented. One with all switches operating with zero voltage switching (ZVS), and another with two switches operating with ZVS and two switches with zero current switching (ZCS). The experimental results are presented along with a performance comparison of the two versions     

A bench-scale study on biodegradation and volatilization of ethylbenzoate in aquifers

Experiments were conducted to investigate the fate of ethylbenzoate and soil microorganisms in shallow aquifers. Biodegradation and volatilization have been identified as the major mechanisms in attenuating ethylbenzoate in contaminated soils. The rate of volatilization was experimentally found to be limited by gas-phase diffusion. The parameters of an available model, i.e., the maximum specific growth rate and the saturation constant, have been estimated by fitting the model to the experimental data obtained with ethylbenzoate as the carbon source; the former was 0.49 h⁻¹, and the latter was 62 mg L⁻¹. Various facets of biodegradation, including the effects of mass-transfer resistance and initial distribution of microorganisms, have been numerically analyzed on the basis of the model.     

Compact design waveguide grating routers

A novel generic design for waveguide grating routers is demonstrated in the InP-InGaAsP material system that reduces the chip size by 50%, while still maintaining relaxed processing tolerances. Experimental results confirm no degradation in device performance for the compact design when compared to conventional devices