Dependence of Output Power on Cavity Length in a Gyrotron Backward Wave Oscillator

A relativistic electron beam (500 keV, 200 A, 10 ns) generated magnetically tunable microwave radiation in a frequency range of 9-13 GHz when it is injected into an X-band rectangular waveguide immersed in a uniform axial magnetic field (4-10 kG). The mechanism of the microwave radiation was identified as the gyrotron backward wave interaction. The output power of the radiated microwave increased exponentially with the increase of the cavity length.     

Isolation of Endotoxin Eliminating Lactic Acid Bacteria and a Property of Endotoxin Eliminating Protein

Recently, many scholars have reported lactic acid bacteria (LAB) functions, such as anticancer activity and anti‐inflammatory activity for intestines. To decrease inflammatory substances such as endotoxins, LAB consumed safely with meals were isolated from food and food ingredients. First, LAB were isolated as 168 strains of bacillus LAB (49 strain) and coccus LAB (119 strains) from food ingredients and fermented foods such as rice, rice bran, malt, grains, miso soy paste, and some pickles. Their LAB (168 strains) were cultivated in medium containing endotoxin from Escherichia coli O18 LPS at 15 and 30 °C for 64 h to identify endotoxin‐eliminating LAB. Consequently, the AK‐23 strain was screened as an endotoxin‐eliminating LAB strain. The strain decreased endotoxin in YP medium without sugar at 30 °C for 64 h until 9% of endotoxin. The strain was identified as Pediococcus pentosaceus according to morphological characteristics such as its cell shape, physiological characteristics related to its fermentation type, assimilation of sugars, pH tolerance, optimum growth temperature, and molecular biological characteristics as its homology to 16S rRNA. To investigate the location of the endotoxin‐eliminating substance, 4 fractions were separated from AK‐23 cells as extracellular, cell wall digestion, cytoplasm, and cell membrane fractions. The endotoxin‐decreasing substance, located on a cell wall, was identified as a 217 kDa protein.     

Development of novel rare earth doped fluoride and oxide scintillators for two-dimensional imaging

Two topics were focused.The first one was about the gamma-ray scintillator,Pr3+:Lu3Al5O12(LuAG) .The second one was about neutron scintillator,Ce3+:6LiCaAlF6 and Eu2+:6LiCaAlF6(6LiCAF) .Those scintillators have been developed very recently for modern imaging appli-cations in the medical and homeland security fields.In both cases,the rare earth ions are playing the crucial role as emission centers.Pr3+ in LuAG provided fast 5d→4f transition providing noticeably shorter decay time than that of Ce3+.Among several candidate hosts,LuAG showed the best performance.Bulk crystal growth,basic scintillation properties,two-dimensional gamma-ray imaging and positron emission mammography(PEM) application were demonstrated.Due to the international situation,the homeland security was compromized by illicit traffic of explosives,drugs,nuclear materials,etc.and the ways to its improvement became an important R&D topic.For this purpose the Ce and Eu doped LiCAF ap-peared competitive candidates.Especially,when substitution of 3He neutron detectors was considered,the discrimination ability of gamma-ray from alpha-ray was important.Bulk crystal growth,basic scintillation properties and two-dimensional neutron imaging were demonstrated.     

Gaussian solar flux model

The Gaussian Solar Flux model (GSFM) predicts instantaneous hourly and integrated daily direct and diffuse solar flux upon sloped as well as horizontal surfaces for clear and cloudy days. Comparison with Davis SEMRTS data from the first six months of 1981 indicates a mean relative error of +/−3.5% and a correlation coefficient of 0.999 for instantaneous global flux during clear days.The GSFM improves upon previous monolayer models with cloud transmittance functions generalized for different surface albedos and a fast Gaussian quadrature based estimate for water vapor pathlengths. Advantages over multilayer models are its speed and lack of need for soundings. Input may be made entirely from standard surface meteorological measurements.     

Status of design and procurement activities in JT-60SA

The JT-60SA experiment is one of the three projects to be undertaken in Japan as part of the Broader Approach Agreement, conducted jointly by Europe and Japan, and complementing the construction of ITER in Europe. It is a fully superconducting tokamak capable of confining break-even equivalent deuterium plasmas with equilibria covering high plasma shaping with a low aspect ratio at a maximum plasma current of I_p = 5.5 MA. In late 2007 the BA Parties, prompted by cost concerns, asked the JT-60SA Team to carry out a re-baselining effort with the purpose to fit in the original budget while aiming to retain the machine mission, performance, and experimental flexibility. Subsequently the Integrated Project Team has undertaken a machine re-optimization followed by engineering design activities aimed to reduce costs while maintaining the machine radius and plasma current. This effort led the Parties to the approval of the new design in late 2008 and hence final design and procurement activities have commenced. The paper will describe the process leading to the re-baselining, the resulting final design and technical solutions and the present status of procurement activities.     

High transconductance selfaligned WSi gate AlInAs/GaInAs HIGFETs grown by MOCVD

HIGFETs were fabricated using an AlInAs/GaInAs heterostructure grown by MOCVD. The 1 mu m-gate HIGFET showed a maximum transconductance of 740 mS/mm at room temperature, which is the highest transconductance obtained for HIGFETs. The reduction of the AlInAs layer thickness to 30 nm and the low source resistance are the primary reasons for this enhancement.<>     

Magneto-optical properties of self-organized strained InGaAs quantum disks

We have measured the optical properties of self-organized strained InGaAs quantum disks in high magnetic fields. The disks are formed during spontaneous reorganization of a sequence of AlGaAs and strained InGaAs epitaxial films grown on GaAs (311)B substrates by metallorganic vapor-phase epitaxy. The magneto-luminescence properties of these InGaAs quantum disks have been studied for various disks sizes with lateral widths from 100 nm down to 20 nm. We have confirmed that when the lateral confinement exists the exciton binding energy increases even when the spatial extent of the effective potential is greater than the exciton in-plane Bohr radius. This enhancement starts being noticeable when the spatial extent of the potential is two, three times larger than the Bohr radius, where the center-of-mass quantization is negligibly small.     

Plasma factor triggering alternative complement pathway activation by liposomes

Several plasma components, such as complement (C) components, play a role in the clearance of liposomes from the circulation. The interactions between liposomes and the C system were investigated in this study. Multilamellar vesicle (MLV) liposomes, which were damaged by activation of the complement, became susceptible depending on the density of cetylmannoside (Man) on the liposome membrane, and activation proceeded through the alternative C pathway as observed for liposomes without Man (PC-MLV) (K. Funato et al., Biochim. Biophys. Acta 1103:198-204, 1992). In addition, the capacity of Man-modified liposomes (Man-MLV) to activate the alternative C pathway was abolished by preadsorption of plasma with Man-MLV but not with PC-MLV. The results suggest that a specific plasma factor adsorbed with Man-MLV was responsible for the augmentation of the C activation and, further, that the rapid clearance of Man-MLV from the circulation is caused by both enhanced C-mediated liposome permeability and enhanced C-mediated phagocytosis of liposomes.