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51.
Matsushima S Sasaki F Kinosada Y Maeda H Sogami M Era S Yatabe Y Miura S Ohsaki H Sakamoto J 《Magnetic resonance imaging》2000,18(4):379-385
A prospective study was performed to investigate the correlations between saturation transfer ratio (STR) and histologic parameters of invasive ductal carcinomas in human breast. The histologic parameters investigated were the extent of fibrosis in the intercellular matrix, dysplastic changes of nuclei, and mitotic index. Twenty-seven patients with breast carcinoma were examined using an off-resonance saturation pulse in conjunction with conventional field-echo T(1)-weighted imaging at frequency offsets of 448 Hz and 1200 Hz from water resonance. The values of STR at frequency offset of 1200 Hz (STR(1200)) increased from non-scirrhous carcinoma to scirrhous carcinoma. Although STR(1200) showed correlation with the extent of fibrosis in the intercellular matrix (p<0.01, n = 27), they did not correlate with the dysplastic changes of nuclei or mitotic index. On the other hand, the values of STR at frequency offset of 448 Hz (STR(448)) demonstrated close correlation to dysplastic changes of nuclei and mitotic index (p<0.01, n = 27). STR(1200) correlates with the structural characteristics and STR(448) correlates with the nature of malignant cells with regard to nuclear dysplasia and mitotic potential. 相似文献
52.
53.
Mutsumi Tashiro Pradeep K. Pujari Shu Seki Yoshihide Honda Shigehiro Nishijima Seiichi Tagawa 《Radiation Physics and Chemistry》2000,58(5-6):587-592
Temperature dependence of positron annihilation lifetime spectra of polysilanes such as, poly(methyl-n-propylsilane) (PMPrS) and poly(di-n-hexylsilane) (PDHS) has been investigated. The τ3 in PMPrS is seen to increase monotonically around the solid–liquid transition temperature. The transition temperature and free volume are observed to depend on the molecular weight and/or packing of the backbones. For PDHS, a sharp change in τ3 and I3 is seen at the solid–solid transition temperature. Free volume radius probability density functions, above and below the transition temperature, are presented in PMPrS and PDHS. Positron studies are complimented by conventional thermal analysis studies. 相似文献
54.
In this paper, we propose a new design for the recursive least-squares (RLS) Wiener fixed-lag smoother and filter in linear discrete-time wide-sense stationary stochastic systems. It is assumed that the signal is observed with additive white observation noise. The signal is uncorrelated with the observation noise. The estimators require knowledge of the system matrix, the observation matrix and the variance of the state vector. These quantities can be obtained from the auto-covariance function of the signal. In the estimation algorithms, moreover, the variance of the observation noise is assumed to be known, as a priori information. 相似文献
55.
56.
T. Matsushima N. Nakajima M. Tamura T. Sueta 《International Journal of Infrared and Millimeter Waves》1986,7(10):1585-1589
A method of expanding the tuning range of the CW CO2 waveguide laser making use of a Fabry-Perot type light modulator is proposed. A preliminary experiment has been done to confirm the workability of the proposed scheme. 相似文献
57.
Lobo AO Corat MA Ramos SC Matsushima JT Granato AE Pacheco-Soares C Corat EJ 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18308-18314
A method for the electrodeposition of hydroxyapatite films on superhydrophilic vertically aligned multiwalled carbon nanotubes is presented. The formation of a thin homogeneous film with high crystallinity was observed without any thermal treatment and with bioactivity properties that accelerate the in vitro biomineralization process and osteoblast adhesion. 相似文献
58.
Yu S Pearson JC Drouin BJ Sung K Pirali O Vervloet M Martin-Drumel MA Endres CP Shiraishi T Kobayashi K Matsushima F 《The Journal of chemical physics》2010,133(17):174317
Complete and reliable knowledge of the ammonia spectrum is needed to enable the analysis and interpretation of astrophysical and planetary observations. Ammonia has been observed in the interstellar medium up to J=18 and more highly excited transitions are expected to appear in hot exoplanets and brown dwarfs. As a result, there is considerable interest in observing and assigning the high J (rovibrational) spectrum. In this work, numerous spectroscopic techniques were employed to study its high J transitions in the ground and ν(2)=1 states. Measurements were carried out using a frequency multiplied submillimeter spectrometer at Jet Propulsion Laboratory (JPL), a tunable far-infrared spectrometer at University of Toyama, and a high-resolution Bruker IFS 125 Fourier transform spectrometer (FTS) at Synchrotron SOLEIL. Highly excited ammonia was created with a radiofrequency discharge and a dc discharge, which allowed assignments of transitions with J up to 35. One hundred and seventy seven ground state and ν(2)=1 inversion transitions were observed with microwave accuracy in the 0.3-4.7 THz region. Of these, 125 were observed for the first time, including 26 ΔK=3 transitions. Over 2000 far-infrared transitions were assigned to the ground state and ν(2)=1 inversion bands as well as the ν(2) fundamental band. Of these, 1912 were assigned using the FTS data for the first time, including 222 ΔK=3 transitions. The accuracy of these measurements has been estimated to be 0.0003-0.0006?cm(-1). A reduced root mean square error of 0.9 was obtained for a global fit of the ground and ν(2)=1 states, which includes the lines assigned in this work and all previously available microwave, terahertz, far-infrared, and mid-infrared data. The new measurements and predictions reported here will support the analyses of astronomical observations by high-resolution spectroscopy telescopes such as Herschel, SOFIA, and ALMA. The comprehensive experimental rovibrational energy levels reported here will permit further refinement of the potential energy surface to improve ammonia ab initio calculations and facilitate assignment of new high-resolution spectra of hot ammonia. 相似文献
59.
N. A. Braga C. A. A. Cairo J. T. Matsushima M. R. Baldan N. G. Ferreira 《Journal of Solid State Electrochemistry》2010,14(2):313-321
Hybrid three-dimensional electrodes produced from microcrystalline boron-doped diamond (BDD) and/or nanocrystalline diamond
films were grown on porous titanium (Ti) substrate by hot filament chemical vapor deposition (HFCVD) technique. Powder metallurgy
technique was used to obtain the Ti substrates provided by interconnected and open pores among its volume. Diamond growth
parameters were optimized in order to provide the entire substrate surface covering including the deeper surfaces, pore bottoms,
and walls. The morphology and structure of these electrodes were studied by scanning electron microscopy (SEM) and visible
Raman spectroscopy techniques, respectively. Electrochemical response was characterized by cyclic voltammetry measurements.
Results showed a wide working potential window and low background current characteristic of the diamond electrodes. The kinetic
parameters also pointed out to a quasi-reversible behavior for these hybrid three-dimensional diamond/Ti electrodes. 相似文献
60.
Tomohiro Suetsuna Seiichi SuenagaShinya Sakurada Koichi HaradaMaki Tomimatsu Toshihide Takahashi 《Journal of magnetism and magnetic materials》2011,323(13):1793-1798
Self-forming core/shell nanoparticles of magnetic metal/oxide with crystalline grain size of less than 40 nm were synthesized. The nanoparticles were highly concentrated in an insulating matrix to fabricate a nanocomposite, whose magnetic properties were investigated. The crystalline grain size of the nanoparticles strongly influenced the magnetic anisotropy field, magnetic coercivity, relative permeability, and loss factor (tan δ=μ″/μ′) at high frequency. The packing ratio of the magnetic metallic phase in the nanocomposite also influenced those properties. High permeability with low tan δ of less than 1.5% at up to 1 GHz was obtained in the case of the nanoparticles with crystalline grain size of around 15 nm with large packing ratio of the nanoparticles. 相似文献