Structure determination of the rutile-TiO2(110)-(1 × 2) surface using total-reflection high-energy positron diffraction (TRHEPD).

The exact structure of the rutile-TiO2(110)-(1 × 2) surface, which had been under debate over the past 30 years, was investigated using the newly developed technique of total-reflection high-energy positron diffraction (TRHEPD), which is a positron counterpart of reflection high-energy electron diffraction (RHEED). The rocking-curves for the 00-spot obtained from the experimental diffraction patterns were compared to the curves for various models calculated with a full-dynamical theory. It was found that the rocking-curves matched those for a surface consisting of a Ti2O3 configuration, originally suggested by Onishi and Iwasawa [H. Onishi and Y. Iwasawa, Surf. Sci., 1994, 313, L783], but with a further modification of atomic positions close to the ones proposed by Wang et al. [Q. Wang, A. R. Oganov, Q. Zhu and X. F. Zhou, Phys. Rev. Lett., 2014, 113, 266101]. This result demonstrates that TRHEPD can distinguish between the existence and absence of the oxygen atoms on the topmost surface, and between the Ti atoms residing in positions at the interstitial-vertical sites and those at interstitial-horizontal sites.

Close correlation between the magnetic moments, lattice distortions, and hybridization in LaMnO3 and La(1-x)Sr(x)MnO3+delta: doping-dependent magnetic circular X-ray dichroism study.

The first observation of a magnetic circular x-ray dichroism (MCXD) at the Mn L2,3 core edges in antiferromagnetic LaMnO3 shows canted spin and orbital ( m(orb)) moments arising from lattice distortions. An L2,3-edge MCXD in ferromagnetic metals and insulators, La1-xSr(x)MnO3+delta, reveals that m(orb) of Mn strongly depends on x in the metallic regime but remains unchanged with the metal-to-insulator transition (x approximately 0.16). An O K-edge MCXD, which shows m(orb) of O caused by 2p-3d hybridization, is much larger in the ferromagnetic metal than insulator phases, sharply contrasting with m(orb) of Mn. Our findings indicate a close magnetism-lattice-hybridization coupling.

Direct determination of interfacial magnetic moments with a magnetic phase transition in Co nanoclusters on Au(111).

The spin, in-plane and out-of-plane orbital and magnetic dipole moments of almost purely interfacial Co atoms were directly determined for Au/2-monolayer Co nanoclusters/Au(111) by angle-dependent magnetic circular x-ray dichroism (MCXD) measurements. The field- and temperature-dependent MCXD evidences a ferromagnetic(FM)-to-superparamagnetic phase transition in single-domain clusters with decreasing size. The interfacial moments are remarkably enhanced as compared with bulk values, verifying theoretical predictions. The FM clusters show strong perpendicular magnetic anisotropy, providing promise of applications for nanoscale magnetic bits.

A compact molecular-beam epitaxy apparatus for in situ soft X-ray magnetic circular dichroism experiments.

An economical and easily movable molecular-beam epitaxy (MBE) apparatus which prepares magnetic ultrathin films and superlattices with atomically well controlled interfaces has been designed and constructed. Cleaning and characterization of substrates, sample deposition in a layer-by-layer fashion, and characterization of samples both during and after growth can be carried out in a single ultrahigh vacuum (UHV) chamber. This MBE apparatus is combined with UHV high-field magneto-optical instruments for in situ soft X-ray magnetic circular dichroism experiments on two-dimensional magnetic systems.

Treatment of a depressive disorder patient with EEG-driven photic stimulation.

This study examined the effects of electroencephalographic- (EEG-) driven photic stimulation on a case of depressive disorder, as measured by a psychometric test of mood states, EEG parameters, and several autonomic indices. The EEG-driven photic stimulation enhances the alpha rhythm of brain waves using photic signals, the brightness of which is modulated by a subject's own alpha rhythm. The patient was a 37-year-old businessman, who was treated for depression with medication during the 13 months prior to his first visit to our hospital. He underwent two sets of inpatient treatment sessions, comprising first 16 and then 18 treatment sessions. The treatments brought about the following changes: an improvement in general mood state, alpha rhythm increase, cardiac parasympathetic suppression, and increased skin conductance level. In addition, significant correlations between alpha rhythm increase and cardiac parasympathetic suppression or cardiac sympathetic predominance were observed with each inpatient treatment. Significant correlations between alpha rhythm increase, cardiac parasympathetic suppression, or cardiac sympathetic predominance and the improvement of general mood state were also observed. Thus, from these observations, it was concluded that the alpha enhancement induced by EEG-driven photic stimulation produced an improvement in the patient's depressive symptomatology connected with cardiac parasympathetic suppression and sympathetic predominance.

[Experimental studies for immunoscintigraphy of adenocarcinoma of the prostate with 125I-labeled monoclonal antibody to gamma-seminoprotein].

We established LNCaP tumor in male nude mice after inoculation of LNCaP cells. The tumor produces the organ-specific glycoproteins in the human prostate, gamma-seminoprotein (gamma-Sm), which has been verified by immunohistochemistry and enzyme immuno assay. The LNCaP tumor is composed of 2 distinct portions, namely GEL/FLUID portion and SOLID portion. The GEL/FLUID portion contains much more gamma-Sm than the SOLID portion does. The monoclonal antibody against gamma-Sm (murine IgG1, K) was radio-labeled with iodine-125 by lactoperoxidase method followed by passage over column chromatography. Finally the conjugates with specific activity of 49.8-56.6 KBq/micrograms were obtained. Biodistribution of 125I-labeled monoclonal antibody to gamma-Sm (125I-gamma MAb) was evaluated by whole-body autoradiography (ARG) and by determination of label uptake (DLU) by the LNCaP tumor using the well type gamma counter. The ARG were obtained 1-9 days after intravenous administrations of 32-38 micrograms of 125I-gamma MAb to 12 nude mice bearing LNCaP tumor. The DLU were evaluated 3, 4 and 7 days after intravenous administrations of 18-25 micrograms of 125I-gamma MAb to 9 nude mice bearing LNCaP tumor. The DLU by organs (GEL/FLUID portion, SOLID portion, liver, kidney, spleen, lung, etc.) were expressed as F-values (%) which were calculated by the following formula: F = radioactivity per gram of tissue (dpm/g) divided by injected dose per gram of animal (dpm/g) x 100 and tissue-to-blood ratios (T/B). The specific uptake by the LNCaP tumors, especially in the GEL/FLUID portion, was observed on ARG, with optimal images of the tumor evaluated 4-7 days after administrations. The F-values and T/B of the LNCaP tumors were always higher than those of other organs. Especially T/B of GEL/FLUID portion were of 6.7 and 6.3, evaluated 4 and 7 days after administration of 125I-gamma MAb respectively. These results suggest that the radio-labeled gamma MAb is applicable for immunoscintigraphy of adenocarcinoma of the prostate.

[Surgical treatment of renal cell carcinoma with tumor thrombus in inferior vena cava].

Removal of renal cell carcinoma (RCC) extended into the inferior vena cava (IVC) can be a difficult operation. Between 1941 and 1989, 110 RCC patients were treated with radical operation and examined for tumor thrombus histopathologically. Twenty nine (26.3%) patients had invasion into the returning vein of tumor (Stage Vla), 12 (10.9%) in renal vein (stage Vlb) and the remaining 4 (3.6%) into IVC (stage V2). In one patient who had surgery under extracorporeal circulation, a thrombus was extended into the right atrium. In the remaining three patients, the RCC was confined to a small portion of the IVC and operated by caval sleeve resection. Radical operation in such patients free of any distant metastasis, may raise the survival rate.

Resuscitation of carbon-contaminated mirrors and gratings by oxygen-discharge cleaning. 2: Efficiency recovery in the 100-1000-eV range.

The capability of dc oxygen-discharge cleaning to resuscitate the efficiencies of mirrors and gratings contaminated by synchrotron radiation has been studied over the 100-1000-eV photon-energy range. The contamination- induced efficiency degradation was severe at the carbon K edge, even for a low contamination level. A large reduction in the mirror reflectance was also observed just below the carbon K edge and at high energies, which was shown by a model calculation to be ascribable to an interference effect in the carbon film. Cleaning resulted in a dramatic recovery of the efficiencies; their increase amounted to more than 1 order of magnitude at these energies. The removal of contaminant deposits also led to a reduced scattering level and a restoration of the grating-blaze effect; these contribute to an improvement in the monochromator performance, both regarding the stray-light level and the diffracted-light intensity.

Resuscitation of carbon-contaminated mirrors and gratings by oxygen-discharge cleaning. in the 4-40-eV range.

The dc oxygen-discharge cleaning of optical elements contaminated by synchrotron radiation has been studied for a variety of contamination levels, optical materials, electrode and reflecting-surface configurations, discharge powers, and exposure times. Cleaning with a proper electrode-surface configuration resulted in the removal of contaminant layers within 1 h even for highly contaminated elements. The reflectance of mirrors and the diffraction efficiency of gratings were almost completely restored after cleaning over the 4-40- eV energy range; the enhancement even amounted to 1 order of magnitude in some cases. This cleaning procedure did not cause any increased roughness; rather, it resulted in a reduced scattering level of contaminated elements. The removal of contaminants also led to a restoration of the grating blaze; essentially, this contributed to an improvement in the inside first-order efficiency around the blazed energy. From the results with controlled power and exposure time, it was shown that an optimum exposure is achieved within several minutes after the disappearance of visible contamination.