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The refractive index and the temperature coefficient of the optical path length change of tellurite (80TeO2:20Li2O) and chalcogenide glasses (72.5Ga2S3:27.5La2O3) were determined as a function of temperature (up to 150 °C) and wavelength (in the range between 454 and 632.8 nm). The tellurite glass exhibits the usual refractive index dispersion in the wavelength range analyzed, while anomalous refractive index dispersion was observed for the chalcogenide glass between 454 and 530 nm. The dispersion parameters were determined by means of the single-effective oscillator model. In addition, a strong dependence of the temperature coefficient of the optical path length on the photon energy and temperature was found for the chalcogenide glass. The latter was correlated to the shift of the optical band gap (or electronic edge) with temperature, which was interpreted by the electron-phonon interaction model. [ABSTRACT FROM AUTHOR]

This paper reports the analytical formulation of a surface wave sustained plasma antenna based on the antenna theory and the theory for a surface wave sustained plasma. The antenna (tube) structure is a basic quarter-wavelength monopole antenna, comparable to a wavelength of a surface wave. The theory for a surface wave sustained plasma in a semi-infinitely long tube is extended to a finite length plasma. The electron density distribution is calculated based on the extended theory, and antenna characteristics are obtained from the electron density distribution. The analytical results obtained from the formulation show good agreement with the numerical results. The electron density in the finite length tube depends on the existence of the interference between forward- and backward-traveling waves and the boundary condition at the tube end. The electron density distribution is determined based on the balance between the forward- and backward-traveling waves. In the case that the plasma does not reach the tube end, which is equivalent to the case of a semi-infinitely long tube, the antenna gain is constant at a low value due to high plasma resistance and low radiation resistance, without the propagation of the backward-traveling wave. Once the plasma reaches the tube end, due to the coexistence of the forward- and backward-traveling waves with their interference, the electron density is elevated fairly beyond the critical density for sustaining surface wave propagation. Consequently, the antenna gain increases with the synergistic effect of the decrease in plasma resistance and the increase in radiation resistance, and the surface wave sustained plasma works as an antenna. [ABSTRACT FROM AUTHOR]

Spin-polarized He + ion scattering spectroscopy (SP-ISS) study on a polycrystalline Sn target surface is reported. We observed substantial spin dependent He + ion scattering on the non-magnetic Sn target. It is not due to He + ion neutralization, but it is attributed to spin–orbit coupling (SOC) that acts transiently on the He + 1 s electron spin in the He + –Sn atom binary collision. We found that the spin dependent scattering quantified as the spin asymmetry exhibits periodic oscillation with the reciprocal of the He + ion velocity. The oscillation originates from the SOC induced-slight energy difference of the [He + –Sn] and [He 0 –Sn + ] systems which are involved in the quasi-resonant charge transfer. The oscillatory spin asymmetry shows that SOC arises from collision induced intermediate state. [ABSTRACT FROM AUTHOR]

We studied low-energy (1.57 keV) electron-spin polarized 4 He + ion scattering on various 5 d transition metal targets. The scattered ion intensity generally differed between the incident He + ions with up and down spins. This spin dependent ion scattering is attributed to the spin–orbit coupling (SOC) that acts transiently on the He + 1 s electron spin in the He + -target binary collision. We observed that the amplitude of the spin dependence in ion scattering, i.e., the spin asymmetry, differs between 5 d transition metal targets. This target element dependence of the spin asymmetry is discussed in terms of re-ionization of He 0 , which originates from the neutralization of the He + ion during the He + -target collision. Since the re-ionization is spin independent process, it degrades the effective spin polarization of the He + ion beam. This explains smaller spin asymmetry with the target on which He 0 is re-ionized with higher rate. [ABSTRACT FROM AUTHOR]

Discusses the clarification of mode conversion process in the Ion Cyclotron Range of Frequencies in a longitudinally inhomogeneous two-ion-species plasma. Detection of the propagation of the slow wave between the ion-ion hybrid resonance and minority ion cyclotron resonance layers; Observation of simultaneous minority ion heating.

Abstract: The splitting of NMR signal, which is analyzed in terms of the invariant hyperfine coupling between the nuclear spin and the multipolar moments of magnetic ions, gives important information about the multipolar ordering. The NMR splitting of P nuclei is analyzed for the low-temperature phase of PrFe4P12, whose nature has been controversial. Two scenarios are examined: one is a modulation of the hyperfine coupling caused by the antiferro-quadrupole (AFQ) ordering; another is the hyperfine coupling due to a monopole-type ordering. [Copyright &y& Elsevier]

Abstract: Recent development of DMFT band calculation for Ce compounds is reported. The auxiliary impurity Anderson model is solved by a method named , which can include the correct exchange process of fluctuation and also the crystalline field (CF) and spin–orbit splitting of self-energy. These are necessary features in the quantitative band theory for Ce compounds. The results of application on CeSb and CeP are presented. The double peaks structure in the photoemission spectra of these compounds is reproduced by the non-empirical calculation. The magnetic excitation spectra are also calculated. It is shown that the CF splitting energy is reversed in CeSb when the temperature decreases. [Copyright &y& Elsevier]

We report here results of DC and AC magnetization, and magnetic specific heat measurements of a geometrically frustrated pyrochlore Tb2Nb2O7. The DC susceptibility χ is consistent with collective paramagnetism down to a temperature scale set by effective nearest-neighbor interactions, Jeff≈–1.5 K. However, AC susceptibility χac peak exhibits a frequency-dependence at Tf∼0.8 K, signaling a spin-glass-like freezing of Tb3+ spins in Tb2Nb2O7. [Copyright &y& Elsevier]

Investigates key features in the high radial confinement mode induced by limiter blasting in the HIEI tandem mirror plasma. Induction of sheared plasma rotation in the high confinement phase; Reduction of edge turbulence; Identification of a hysteresis phenomenon as a function of bias voltage or bias current.

We have measured the density of metastable He atoms in the lowest triplet state (23S1) with a diode-laser absorption spectroscopic technique in atmospheric pressure plasmas produced by dielectric barrier discharge schemes. Two different types of electrode configuration are employed: one is a conventional parallel-plate system and the other is a microdischarge integrated system with stacked metal-mesh electrodes covered by insulating films. We have analyzed the pressure-broadened spectral line corresponding to the 23S1→23PJ (J=0–2) transition to derive the broadening coefficient and to calibrate absolute densities. The measured density ranges from 1011 to 1012 cm-3, but the values in the mesh-type system are larger than those in the parallel-plate system by about one order of magnitude. The density, however, depends strongly on the gas flow rate, showing the influence of quenching by the Penning-ionization process with impurities. Those behaviors are consistent with the variation of the electron density estimated by millimeter-wave transmittance measurement. [ABSTRACT FROM AUTHOR]

Surface magnetism is analyzed by spin-dependent He+-ion neutralization (the Auger neutralization) in the vicinity of a surface using an electron spin-polarized low-energy He+-ion beam [spin-polarized ion scattering spectroscopy (SP-ISS)]. Recently, spin-orbit coupling (SOC) has been found to act as another mechanism of spin-dependent low-energy He+-ion scattering. Thus, it is crucial for surface magnetism analyses by SP-ISS to separate those two mechanisms. In the present study, we investigated the spin-induced asymmetry in scattering of low-energy He+ ions on ultrathin Au and Sn films as well as the oxygen adsorbate on a magnetized-Fe(100) surface where these two mechanisms may coexist. We found that the Fe surface magnetism immediately disappeared with the growth of those overlayers. On the other hand, we observed no induced spin polarization in the Au and Sn thin films even in the very initial stage of the growth. We also observed that the spin asymmetry of the O adsorbate was induced by the magnetism of the underlying Fe substrate. The present study demonstrates that the two mechanisms of the spin-asymmetric He+-ion scattering (the ion neutralization and SOC) can be separated by an azimuthal-angle-resolved SP-ISS measurement. [ABSTRACT FROM AUTHOR]

Plasma jet discharges are shown to be enhanced significantly, with respect to emission intensity, in the presence of ellipsoidal microcavities dispersed at uniform intervals along the gas flow channel. In these experiments, 25 microcavities were fabricated in the top and bottom faces of a gas flow channel having a rectangular cross section. Conducting film electrodes exterior to the glass structure, powered by a 20-kHz sinusoidal voltage, produced plasma along the entire channel as well as within the microcavities. Stronger optical emission and longer plasma jets were observed in this system than in an equivalent plasma jet system without microcavities. [ABSTRACT FROM AUTHOR]

We studied low-energy (∼ 1.55 keV) electron-spin-polarized4He+ion scattering on a Bi(111) ultrathin film epitaxially grown on a Si(111) substrate. We observed that the scattered ion intensity differed between the incident He+ions with up and down spins even though Bi is a non-magnetic element. To analyze the origin of this spin-dependent ion scattering (the spin asymmetry), we investigated the detailed relationship between the spin asymmetry and the incident angle, the azimuthal angle, the scattering angle, and the incident energy. All the data indicate that the spin asymmetry originates from the scattering cross section owing to the non-central force in the He+–Bi atom binary collision. The non-central force is most likely attributed to the spin–orbit coupling that acts transiently on the He+1s electron spin in the binary collision. [ABSTRACT FROM PUBLISHER]

Abstract: The photoemission spectrum (PES) of is calculated by using the non-crossing approximation for the impurity Anderson model, in which the intensity of the pf-mixing is estimated by the LMTO band calculation for . The large intensity of PES just below the Fermi level can be explained in terms of many multiplets that accompany a hole in the valence band. The temperature dependence of PES is consistent with dominant intermediate states rather than ones. [Copyright &y& Elsevier]

This paper reports radiation characteristics of input power from a surface wave sustained plasma antenna investigated theoretically and experimentally, especially focusing on the power consumption balance between the plasma generation and the radiation. The plasma antenna is a dielectric tube filled with argon and small amount of mercury, and the structure is a basic quarter wavelength monopole antenna at 2.45GHz. Microwave power at 2.45 GHz is supplied to the plasma antenna. The input power is partially consumed to sustain the plasma, and the remaining part is radiated as a signal. The relationship between the antenna gain and the input power is obtained by an analytical derivation and numerical simulations. As a result, the antenna gain is kept at low values, and most of the input power is consumed to increase the plasma volume until the tube is filled with the plasma whose electron density is higher than the critical electron density required for sustaining the surface wave. On the other hand, the input power is consumed to increase the electron density after the tube is fully filled with the plasma, and the antenna gain increases with increasing the electron density. The dependence of the antenna gain on the electron density is the same as that of a plasma antenna sustained by a DC glow discharge. These results are confirmed by experimental results of the antenna gain and radiation patterns. The antenna gain of the plasma is a few dB smaller than that of the identical metal antenna. The antenna gain of the plasma antenna is sufficient for the wireless communication, although it is difficult to substitute the plasma antenna for metal antennas completely. The plasma antenna is suitable for applications having high affinity with the plasma characteristics such as low interference and dynamic controllability. [ABSTRACT FROM AUTHOR]

To review diffusion abnormalities seen in diffusion-weighted MRI in neurological pathologies. We examine the clinical significance of the abnormalities in a broad spectrum of neurological diseases and highlight our current understanding of their causes. Diffusion abnormalities seen on diffusion-weighted MRI can play an important role in the diagnosis and follow-up of a broad spectrum of neurological diseases. A thorough understanding of the appearance and significance of these abnormalities is critical in patient management. [ABSTRACT FROM AUTHOR]

Abstract: Anodic porous alumina (APA) films have a honeycomb cell structure of pores and a voltage-induced bi-stable switching effect. We have applied conducting atomic force microscopy (CAFM) as a method to form and to disrupt current paths in the APA films. A bi-polar switching operation was confirmed. We have firstly observed terminals of current paths as spots or areas typically on the center of the triangle formed by three pores. In addition, though a part of the current path showed repetitive switching, most of them were not observed again at the same position after one cycle of switching operations in the present experiments. This suggests that a part of alumina structure and/or composition along the current paths is modified during the switching operations. [Copyright &y& Elsevier]

Ce 4f electronic states in an antiferromagnetic Kondo compound CePd[sub 2]Si[sub 2] and a strong intermediatevalence compound CeNi[sub 2]Si[sub 2] have been investigated by means of high-resolution Ce 4d-4f resonant photoemission spectroscopy at 12 K. The relative intensity of the f[sub 5/2]¹ to f[sub 7/2]¹ final state in the Ce 4f spectrum for CeNi[sub 2]Si[sub 2] is stronger than the relative intensity for CePd[sub 2]Si[sub 2], indicating that the intensity of Kondo resonance scales the Kondo temperature since the Ce 4f spectrum near the Fermi level dominantly reflects the bulk component. Both Ce 4f spectra have been well fitted by the spectral calculations based on a single impurity Anderson model with consideration of the bulk and surface components. Our present calculation indicates that the model is applicable to the analyses of the Ce 4f spectra of the weakly and strongly hybridized systems. [ABSTRACT FROM AUTHOR]

Aim: To investigate the value of machine learning-based multiparametric analysis using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography (FDG-PET) images to predict treatment outcome in patients with oral cavity squamous cell carcinoma (OCSCC).Materials and Methods: Ninety-nine patients with OCSCC who received pretreatment integrated FDG-PET/computed tomography (CT) were included. They were divided into the training (66 patients) and validation (33 patients) cohorts. The diagnosis of local control or local failure was obtained from patient's medical records. Conventional FDG-PET parameters, including the maximum and mean standardised uptake values (SUVmax and SUVmean), metabolic tumour volume (MTV), and total lesion glycolysis (TLG), quantitative tumour morphological parameters, intratumoural histogram, and texture parameters, as well as T-stage and clinical stage, were evaluated by a machine learning analysis. The diagnostic ability of T-stage, clinical stage, and conventional FDG-PET parameters (SUVmax, SUVmean, MTV, and TLG) was also assessed separately.Results: In support-vector machine analysis of the training dataset, the final selected parameters were T-stage, SUVmax, TLG, morphological irregularity, entropy, and run-length non-uniformity. In the validation dataset, the diagnostic performance of the created algorithm was as follows: sensitivity 0.82, specificity 0.7, positive predictive value 0.86, negative predictive value 0.64, and accuracy 0.79. In a univariate analysis using conventional FDG-PET parameters, T-stage and clinical stage, diagnostic accuracy of each variable was revealed as follows: 0.61 in T-stage, 0.61 in clinical stage, 0.64 in SUVmax, 0.61 in SUVmean, 0.64 in MTV, and 0.7 in TLG.Conclusion: A machine-learning-based approach to analysing FDG-PET images by multiparametric analysis might help predict local control or failure in patients with OCSCC. [ABSTRACT FROM AUTHOR]

In this study, we examined the effects of macrophage-colony stimulating factor (M-CSF) on glomerular macrophages in lipopolysaccharide (LPS)-induced murine nephritis. Mice injected intraperitoneally with either M-CSF plus LPS, LPS alone, M-CSF alone or saline every day for 8 days were examined for the degree of urine albumin excretion and lymphocyte-function associated antigen-l-positive (LFA-l+) cells in peripheral blood as well as renal pathology. From our results, LPS or M-CSF combined with LPS emphasized the degree of proteinuria, glomerular deposition of immunoglobulins and mesangial proliferation, associated with accumulation of macrophages in the glomeruli. However, in immunohistological examination of kidneys from these nephritic mice, neither intercellular adhesion molecule-1 (lCAM-1), which may play an important role in the recruitment of macrophages into glomeruli, M-CSF receptor nor the number of LFA-1+ cells in peripheral blood was enhanced by M-CSF. On the other hand, M-CSF alone induced neither proteinuria nor any pathological changes and did not increase the number of glomerular Mac-1+ cells above that in saline-treated controls. These results indicate that M-CSF does not directly cause glomerulonephritis but might participate in accelerating the glomerular inflammatory process by stimulating a potent chemoattractant to recruit monocytes-macrophages into the glomeruli. [ABSTRACT FROM AUTHOR]

Jak3 is a member of the Janus kinase family which plays an important role in cytokine signal transduction. Jak3 associates the γc chain of receptors for IL-2, IL-4, IL-7, IL-9 and IL-15, and is essential for the signal transduction of these cytokines. We have isolated Jak3 kinase from renal mesangial cells and demonstrated the constitutive expression of Jak3 in glomeruli in vivo. To investigate the physiological and pathological role of Jak3 in glomeruli, we prepared anti-Jak3 antibody and analysed the localization of Jak3 in glomeruli of renal biopsy samples from various nephritis patients and normal subjects. Among 61 nephritis patients and four normal subjects investigated in the present study, Jak3 was selectively localized to glomerular epithelia of IgA-N patients (14/34 cases) and focal glomerulosclerosis patients (1/5 cases), but not detected in minimal changes (n = 6), membranous glomerulonephropathy (n = 7), crescentic glomerulonephritis (n = 4), lupus nephritis patients (n = 5), and normal subjects (n = 4). The intense immunoreactivity for Jak3 is significantly associated with the decrease in creatinine clearance (81.5 ± 10.4 ml/ min versus 104 3 ± 29.6ml/min; P < 0.05, Student's t-test) and the increase in level of serum creatinine (1.13 ± 0.33 mg/dl versus 0.75 ± 0.23 mg/dl; P < 0.01, Student's t-test) in IgA-N patients. Furthermore, γc chain was concomitantly expressed with Jak3 in glomerular epithelia in vivo and in vitro, suggesting that signal transduction via γc-Jak3 cascade may be involved in the pathogenesis of glomerular injury of IgA-N. Taken together with the recent findings that IL-4-secreting T lymphocytes in affected giomeruli injure glomerular epithelium, the responsiveness of glomerular epithelium for IL-4 may be pathologically enhanced in IgA-N. [ABSTRACT FROM AUTHOR]

Although prostaglandins have been shown to inhibit the evolution of the nephritis in NZB/W mice, the mechanisms of this effect are unknown. To characterize such inhibition, we injected the prostacyclin (PGI2) analogue. beraprost, into NZB/W mice, using 0.5 mg, 1.0 mg or 5.0 mg beraprost/kg body weight of test animals three times in 1 week when the mice were 2 months old. Evaluation included measurement of urine albumin excretion, serological parameters and splenic T cell subset, as well as examination of renal histology by light and fluorescence microscopy. Mice given beraprost showed a marked decrease in urine albumin excretion and in glomerular hypercellularity compared with untreated controls. Maximal beneficial effects occurred when the dose was 5.0 mg/kg of beraprost. These effects correlated with a reduction of immune complex deposition in glomeruli. In addition, beraprost reduced serum levels of immunoglobulins and anti-double-stranded DNA antibodies, and decreased the number of helper (L3T4+) T cells in splenocytes. These results indicate that beraprost attenuates the nephritis of NZB/W mice, and that the source of this effect is the reduced production of autoantibodies and deposition of immune complexes in glomeruli. [ABSTRACT FROM AUTHOR]

Examines the treatment of IgA nephropathy using novel therapeutic strategy. Preventing nephropathy through local delivery of anti-inflammatory cytokine into glomeruli; Site-specific gene delivery into inflamed glomeruli using a bone marrow-derived cells as vehicle which possesses the ligand of adhesion molecules; Feasibility of the site-specific gene system as therapy for experimental glomerunephritis; Several problems to address before making major investments for clinical use of the site-specific gene system for nephropathy.

Examines the role of osteopontin (OPN) expression in proximal tubular cells in the long-term prognosis of IgA nephropathy. Study method; Analysis of incidence of end-stage renal disease (ESRD); Association of the OPN expression in proximal tubular cells with progression.