Properties of OV Spectral Lines in Ionizing and Recombining Plasmas

A collisional-radiative model for Be-like oxygen ions has been constructed for OV plasmaspectroscopy. The model takes into account recombination processes as well as collisional ionization, radiative transitions, and collisional excitation/deexcitation. Two sets of atomic data are used for comparison. We obtain OV line intensities as functions of electron temperature and density. The line intensity ratios of 2s3s 35 - 2s3p \u27Pr=o.r., are measured in LHD plasmas and are consistent with our models. The line intensity ratio of 2s2p 3P - 2p"P and 2s2 tS - 2s2p rP in recombining plasma is an increasing function of temperature and one measured in the LHD plasma indicates electron temperature less than 7eV. The ratios measured in steady-state phase are larger than I and difficult to explain with the current model

Feeding Deterrence to Reticulitermes speratus (Kolbe) by Fibroporia radiculosa (Peck) Parmasto 1968

Brown rot fungus Fibroporia radiculosa (Peck) Parmasto grown in decayed wood and non-wood material, potato dextrose agar (PDA) media, deterred Reticulitermes speratus (Kolbe) feeding. Decayed wood and PDA media were extracted and tests were performed to assess termite feeding behavior towards the extracts. We found that the extract from PDA media also suppressed termite feeding, although it did not induce mortality. Using gas chromatography and mass spectrometry analysis, two bioactive compounds were detected from the decayed wood extract, and one was detected from the PDA extract. Based on National Institute of Science and Technology (USA) Mass Spectral library match and compound fragmentation, both of the compounds belong to the sesquiterpenes family

Systematic observation of EUV spectra from highly charged lanthanide ions in the Large Helical Device

We have systematically observed extreme ultraviolet (EUV) spectra from highly charged ions of nine lanthanide elements with atomic numbers from 60–70 in optically thin plasmas produced in the Large Helical Device (LHD). Discrete spectral features with isolated lines from relatively higher charge states around Cu-like ions are observed under high temperature conditions around 2 keV,while narrowed quasicontinuum features from charge states around Ag-like ions are observed under low temperature conditions below 1 keV. The positions of the lines and the quasicontinuum features systematically move to shorter wavelengths as the atomic number increases. The wavelengths of the main peaks in the quasicontinuum features agree well with those of singlet transitions of Pd-like ions reported previously. We have easily identified discrete spectral lines from Cu-like and Ag-like ions, some of which are experimentally identified for the first time in the LHD. Their wavelengths are compared with theoretical calculations using a GRASP family of atomic codes. The theoretical valuesare synthesized to the LHD experimental data for the cases of Ag- and Pd-like ions

Temperature dependent EUV spectra of Gd, Tb and Dy ions observed in the Large Helical Device

We have observed a number of different types of extreme ultraviolet (EUV) spectra from highly charged gadolinium (Gd), terbium (Tb) and dysprosium (Dy) ions in optically thin plasmas produced in the Large Helical Device at the National Institute for Fusion Science. Temporal changes in EUV spectra in the 6–9 nm region subsequent to the injections of solid pellets were measured by a grazing incidence spectrometer. The spectra rapidly change from discrete features into unresolved transition arrays (UTAs) following a drop in the electron temperature after the heating power is reduced. In particular, extremely narrowed UTA features, which comprise spectral lines of Ag-like, Pd-like and neighboring ion stages, are observed when the peak electron temperature is less than 0.45 keV due to the formation of hollow plasmas. Some discrete spectral lines of Cu-like and Ag-like ions have been identified in the high and low temperature plasmas, respectively, some of which are experimentally identified for the first time

2D-Time of Flight MR Angiography in Intrathoracic Masses

正常ボランティア5例, 胸部腫瘤性病変の患者15例に対してMR Angiographyを施行した.MRAは, 6秒の息、止めでFLASH法(TR=20msec, TE=8msec, Flip angle=30°)を用いて撮像した像から作成した.全ての症例で胸部大動脈, 上大静脈, 下大静脈, 肺動脈及び肺静脈根部など太い血管の明瞭なMRA像が得られ, 腫瘤とそれら大血管系との関係が把握しやすく胸部腫瘤性病変の評価に有用と考えられた.MR Angiography of the thorax was performed in 5 healthy volunteers and 15 patients with intrathoracic masses. 2D-MRA was obtained sequentially by means of a fast low angle shot(FLASH)technique(TR=20msec.TE=8msec, Flip angle=30within a 6-second period of breath holding. MRA for great vessels was successfully completed in all volunteers and all patients. The relation between tumor and vasculature can be visualized so definitely that MRA may be thought to be a promising complement to MR imaging in the evaluation of intrathoracic masses

放射線画像用X線源の限界性能

線形加速器からの電子線を用いるX線発生装置のターゲット(タングステン)の特性に関して、設計上の問題が定量的に評価可能かを検討した。X線は発生装置の設計の立場からは、(1)発生したX線の焦点特性、(2)ターゲットによる吸収エネルギー、(3)光中性子の発生、等が問題となる。以上のような特性を評価するため中性粒子輸送のモンテカルロプログラムMCNPを用いて、ターゲットに高エネルギー電子を打ち込むシミュレーションを行い、上にのべた評価が可能であるとの結論が得られた

Functional Loss of the HTLV-I Tax Protein Encoded by Variant Proviruses in Infected Individuals.

Accumulating evidence has indicated the presence of HTLV-I quasispecies in infected individuals. To elucidate their biological consequences, we amplified the whole Tax open reading frame (ORF) of HTLV-I proviruses by nested PCR from six infected individuals, including three HAM/TSP patients, and a cloned HTLV-I DNA, pMT2, and the products were introduced into an expression vector. The potential for transcriptional transactivation of protein products of independent 20-39 tax clones derived from each sample was evaluated by transfecting into pA18G-BHK-21 cells containing the HTLV-I LTR-driven lacZ gene. While all of 30 clones derived from pMT2 gave positive results, significant proportions, ranged between 16.0 and 35.0%, of the tax clones from the infected indiv iduals were functionally defective. The functional loss of these tax clones was confirmed by chloramphenicol acetyltransferase (CAT) assay in cells cotransfected with an HTLV-I LTR-CAT reporter. DNA sequence analysis revealed that the defective clones contained at least one nonsynonymous nucleotide substitutions from the consensus sequences of the individual. These findings strongly suggested that the accumulation of HTLV-I proviruses with defective tax was a common feature among infected individuals. Since the Tax protein is indispensable for viral replication, these defective viruses were likely to be generated in individuals after the event of infection. It is conceivable that the quasispecies plays a key role in the latency of HTLV-I infection and possibly in HTLV-I-related pathogenesis

Density evaluation of tungsten W24+, W25+, and W26+ ions using unresolved transition array at 27–34 Å in Large Helical Device

The extreme ultraviolet (EUV) spectra of a tungsten unresolved transition array (UTA) at 15–70 Å have been studied in Large Helical Device (LHD) by injecting a tungsten pellet. Vertical profiles of the UTA line are measured with a space-resolved EUV spectrometer. In our previous study, it has been found that the UTA line at wavelength intervals of 32.16–33.32, 30.69–31.71, and 29.47–30.47 Å is composed of a single ionization stage of W24+, W25+, and W26+, respectively. In this report, therefore, the densities of W24+, W25+, and W26+ ions are evaluated from the radial profile measured at the above-mentioned wavelength intervals. To evaluate ion density, the photon emission coefficients of W24+, W25+, and W26+ ions are calculated using a collisional-radiative (CR) model. The chord-integrated radial profile of UTA lines is converted to a local emissivity profile using the Abel inversion technique. The density profiles of W24+, W25+, and W26+ ions are thus obtained from the local emissivity profile and the photon emission coefficient in addition to the temperature and density profiles. The obtained density profile of the W24+ ion is analyzed in detail by investigating the dependences of the electron density and the number of tungsten particles injected by the tungsten pellet. The total tungsten ion density nW near ρ = 0.7 where the W24+ ion locates is also estimated from the W24+ ion density with fractional abundance in ionization equilibrium calculated with the Atomic Data and Analysis Structure (ADAS) code. The nW evaluated from the present CR model seems to be larger than that estimated from the number of tungsten particles injected by the pellet. Discussions are made with the nW evaluated from the photon emission coefficient in the CL version of the ADAS code