Narrow spectral linewidth characteristics of monolithic integrated-passive-cavity InGaAsP/InP semiconductor lasers

The spectral linewidth of 1.3 ?m monolithic integrated-passive-cavity (IPC) semiconductor laser is measured by a delayed self-heterodyne technique. It is found that the line-width is narrowed when longitudinal submode is suppressed. The narrowest linewidth obtained so far is 900 kHz at 6 mW output power.     

Demonstration of a fully spatial coherent X-ray laser at 13.9 nm

We have recently reported the successful development of a fully coherent X-ray laser (XRL) at 13.9 nm by an oscillator-amplifier configuration with two targets. In the experiment, a seed XRL beam from the first target is injected into a plasma amplifier at the second target. The observed XRL beam has full spatial coherence and 0.2 mrad of nearly diffraction-limited divergence. In order to improve the output fluence, the amplification properties of the XRL beam have been investigated using various plasma lengths of the second amplifier target. The output energy has been improved by a factor of ten, increasing the length of the gain region to 10 mm, resulting in about 0.2 /spl mu/J of output energy.     

A novel DNA polymerase family found in Archaea

One of the most puzzling results from the complete genome sequence of the methanogenic archaeon Methanococcus jannaschii was that the organism may have only one DNA polymerase gene. This is because no other DNA polymerase-like open reading frames (ORFs) were found besides one ORF having the typical alpha-like DNA polymerase (family B). Recently, we identified the genes of DNA polymerase II (the second DNA polymerase) from the hyperthermophilic archaeon Pyrococcus furiosus, which has also at least one alpha-like DNA polymerase (T. Uemori, Y. Sato, I. Kato, H. Doi, and Y. Ishino, Genes Cells 2:499-512, 1997). The genes in M. jannaschii encoding the proteins that are homologous to the DNA polymerase II of P. furiosus have been located and cloned. The gene products of M. jannaschii expressed in Escherichia coli had both DNA polymerizing and 3'-->5' exonuclease activities. We propose here a novel DNA polymerase family which is entirely different from other hitherto-described DNA polymerases.     

Preparation of CdSSe-ZnS superlattice,SrS, and CdSSe-SrS superlattice by hot-wall epitaxy,and applications to electroluminescent devices

CdSSe (manganese-doped, E_g = 1.9–2.5 eV, lattice constant a = 6.05–5.8A)-ZnS (Eg = 3.56 eV, a = 5.41A) superlattices, SrS (cerium-doped, E = 4.4 eV, a = 6.02A) layers, and CdSSe-SrS (cerium-doped) superlattice layers nave been prepared by hot-wall epitaxy, and the properties and the electroluminescent device characteristics of the active layers are reported. For the superlattices with ZnS, the maximum luminance was 800 cd/m² at an applied sinusoidal voltage (V_o-p = 200 V) with frequency 1kHz, and the wavelength of the spectral peak was 610 nm due to the large strain caused by the lattice mismatch (8–15%) between the CdSSe and ZnS layers. The maximum luminance and Comisson Internationale de Enluminure (CIE) chromaticity of CdS(Mn)-ZnS superlattices and CdSe(Mn)-ZnS superlattice devices were 557cd/m² and (x,y) = (0.58,0.41) and 982 cd/m² and (0.61, 0.38), respectively. For superlattices with SrS, the maximum luminance of the device with the SrS (cerium-doped) active layer was nearly 700 cd/m² at a voltage of 340V. Blue electroluminescent emission was observed in the photon wavelength region less than 450 nm, due to carriers dropping into the quantum wells of the device with the CdSSe-SrS superlattice active layer.     

A long-term follow-up study of serial magnetic resonance images in patients with delayed encephalopathy after acute carbon monoxide poisoning

We report a case of vasculitis in a 67-year-old woman who successively developed over a four-month period clinical manifestations suggestive of rheumatoid arthritis, lupus, sicca, syndrome and finally giant cell arteritis. All her symptoms resolved promptly upon discontinuation of enalapril and none recurred over the five-year follow-up period. The only residual manifestation is Jaccoud's arthropathy of the hands.     

High-field conduction and carrier traps in polyethylene copolymerized with various monomers

The electrical breakdown and electrical conduction of ethylene copolymers have been studied. The electric strength of ethylene copolymers containing an optimum content of halogen moieties such as bromophenyl and fluoroethylene groups was found to be higher than that of LDPE over the wide temperature range from ?196°C to 90°C. Also, conduction currents in the copolymers were suppressed at high electric fields. X-ray-induced thermally stimulated currents (TSC) revealed that halogen comonomers act as carrier traps with a depth of about 0.4 eV. Consequently, the introduction of comonomer-containing halogen groups into polyethylene suppresses electron acceleration as a result of an increase in trapping and scattering of conduction electrons. This leads to an increase in electric strength which is determined by the electron avalanche breakdown.     

Myocardial recovery through ECMO after repair of total anomalous pulmonary venous connection: the importance of left heart unloading

A 7-day-old boy who had been placed on extracorporeal membrane oxygenation on his second day of life developed biventricular failure after undergoing surgical repair of a supracardiac variant of total anomalous pulmonary venous connection. Extracorporeal membrane oxygenation was again necessary for postoperative cardiopulmonary support. However, severe left ventricular failure made it imperative to leave the vertical vein open during support in order to decrease pressure on the left ventricle. The patient was successfully weaned from extracorporeal membrane oxygenation on day 8 after surgery and discharged from the hospital on day 23.     

High-power, wide-temperature range operation of 1.3-/spl mu/m gain-coupled DFB lasers with automatically buried InAsP absorptive grating

DFB lasers operating at 1.3 /spl mu/m with gain-coupling structure show single-mode operation over a wide temperature range of -20/spl sim/85/spl deg/C and up to a high power of 130 mW. These lasers have InAsP absorptive grating, which can be formed by a substantially simplified fabrication process, involving annealing a corrugated InP substrate in an atmosphere of mixed arsine and phosphine.