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A 70-year-old Japanese man presented at our hospital with an asymptomatic, blackish, irregularly shaped plaque with a gray nodule in the periphery on his left lower leg. The lesion had been present for 10 years and had recently enlarged, associated with bleeding. Histopathologically, the tumor consisted of three distinct parts: The first part showed massive aggregation of basophilic basaloid cells with peripheral palisading and abundant melanin granules, and was diagnosed as solid-type basal cell carcinoma. The second part showed aggregation of clear cells with squamous eddies, and was diagnosed as proliferating trichilemmal tumor. The third part showed reticular aggregation of basaloid cells with infundibular cysts in the papillary dermis, and was diagnosed as infundibulocystic basal cell carcinoma. We diagnosed this tumor as basal cell carcinoma with various forms of hair follicle differentiation, including differentiation into the outer root sheath.

We studied the growth of graphene by molecular beam epitaxy (MBE) using ethylene and evaluated the MBE-grown graphene. The flow rate dependence of the carbon deposition rate in the ethylene MBE indicated a gradual decrease of the deposition rate with increasing flow rate. This is an improvement from that deposition rate with ethanol, which abruptly decreases because of an etching effect. This feature of ethylene enhances the condition for the growth of the high-quality graphene. Raman spectroscopy measurement and atomic force microscopy observation show that the quality of graphene grown using ethylene is improved from that grown using ethanol from the viewpoints of a domain size and crystallinity. These results demonstrate the advantages of ethylene over ethanol in the MBE growth of graphene.

To evaluate graphene grown by a new method based on gas-source molecular beam epitaxy (MBE), in which a cracked-ethanol source is employed, from the macroscopic viewpoint, we investigated crystal truncation rod scattering by x-ray reflectivity measurement. From the analysis of the x-ray reflectivity data, we found that the MBE-grown graphene forms a layered atomic structure from the macroscopic view, too. The average spacing of the MBE-grown graphene was 3.39 A, which is larger than the interlayer spacing values for bulk crystalline graphite, and the height distributions of the MBE-grown graphene were relatively large. The occupancies of the graphene are smaller than unity and are smaller than that of its underlying graphene, suggesting that graphene did not grow in a layer-by-layer manner but in a three dimensional one, while each layer grew laterally. These results indicate that our new approach is feasible for the formation of wafer-scale graphene, although further improvement of the quality of the graphene by optimizing the growth condition is needed. [DOI: 10.1380/ejssnt.2011.58]

Hydrogen-terminated diamond surface exhibits p-type conductivity during its exposure to air. To investigate this phenomenon, we examined the influence of different gases on the surface conductivity. Exposure to NO 2 gas resulted in the biggest increase in conductivity, while H 2 O vapor decreased the surface conductivity. Moreover, even very low concentrations of NO 2 molecules in air increased the hole sheet concentration, and with increasing NO 2 concentration, the hole sheet concentration increased up to 2.3 × 10 14 cm − 2 (at 300 ppm NO 2 ). This increase of hole sheet concentration was observed during exposure to NO 2 gas and simultaneous adsorption of NO 2 molecules on the diamond surface, while it decreased when the exposure stopped and NO 2 molecules desorbed from the surface. X-ray photoelectron spectroscopy investigation showed upward band bending and partial oxidation of the hydrogen-terminated surface after exposure to air and NO 2 . FETs exposed to NO 2 gas exhibited lower source and drain resistances, which led to a 1.8-fold increase of maximum drain current, transconductance increased 1.5-fold and maximum frequency of oscillation increased 1.6-fold.

Overexpression of class III beta-tubulin (TUBB3) is an important mechanism of taxane resistance. Using 7 melanoma cell lines, 2 normal neonatal human epidermal melanocyte (NHEM) cultures, and 49 primary melanomas, we investigated TUBB3 expression, its relationship to chemosensitivity to taxane derivatives, and the epigenetic mechanism controlling TUBB3 gene expression. Normal melanocytes in vitro and in vivo strongly expressed TUBB3 protein. NHEMs exhibited marked chemoresistance to paclitaxel-induced apoptosis. A subset (10 of 49, 20%) of primary malignant melanomas was TUBB3 negative. The incidence of TUBB3-negative melanomas increased with stage of progression. TUBB3 protein expression varied among cell lines; one (HMV-I) of the seven cell lines exhibited an extremely low endogenous level. TUBB3 protein expression correlated well with chemosensitivity to paclitaxel-induced apoptosis (P0.05). Treatment with a histone deacetylase (HDAC) inhibitor restored TUBB3 expression in HMV-I. Chromatin immunoprecipitation assays revealed that histones H3 and H4 were hypoacetylated at the TUBB3 gene in HMV-I as compared with a TUBB3-overexpressing cell type (HMV-II). Treatment with the HDAC inhibitor induced gain of histone acetylation only in HMV-I. These results suggest that loss of TUBB3 protein may be induced by histone deacetylation in a subset of malignant melanomas, and may be associated with chemosensitivity to taxane.

We describe the behavior of iron and cobalt catalysts on silicon substrates in chemical vapor deposition (CVD) of carbon nanotubes. Nanoparticles of iron and cobalt exhibited a melting point drop in methane ambient. Nanoparticles present after nanotube growth are identified as Fe3C and Co3C, for iron and cobalt, respectively. These findings indicate that a eutectic compound of metal and carbon is formed in the methane ambient, resulting in the phase separation of graphite (nanotubes) as the carbon uptake in the catalyst melt increases. This supports the vapor-liquid-solid mechanism for the nanotube growth by CVD. Iron- or cobalt-silicide formation causes poisoning of the catalysts. However, the coexistence of oxygen due to native oxide on the silicon surface or the metal surface causes formation of a SiO2 base that can prevent silicidation of iron particles.

We describe the development of an equipment which can be employed for examining various surface phenomena in real-time by performing time-resolved core-level photoelectron spectroscopy. We demonstrate this unique capability by examining the desorption of Sb atoms occurring from GaSb(001) as well as Sb/GaAs(001) in the temperature range of 440oC∼580oC, which is the usual growth temperature. The time dependence of core-level photoelectron spectra revealed that the activation energy for Sb desorption varies from 0.7 eV to 2.5 eV due to the difference in local bonding structures. In addition, experiments on alternating growth of GaAs suggest that there are two Ga adsorption sites, the occupation of which is dependent on the Ga coverages. This finding is in agreement with theoretical studies. These results demonstrate the potential of the technique to elucidate the surface process by real-time analysis.

We have developed a submicron-area high energy resolution photoelectron spectroscopy system equipped with a multilayer-coated Schwarzschild objective for forming a soft x-ray microbeam. We show the photoelectron microspectroscopy results of the cross section of a semiconductor double heterostructure sample, namely an epitaxial film [InP (50 nm thick)/ In0.53Ga0.47As (2.3 μm thick)/InP (100) substrate] grown by metalorganic chemical vapor deposition. The core-level photoelectron spectra were obtained from the cross section of the cleaved sample. The As 3d, Ga 3d, and In 4d peaks were observed in the In0.53Ga0.47As region. In the InP region, the As 3d and Ga 3d peaks were not observed, and only the In 4d peak was. This result corresponds to the structure observed by cross-sectional scanning electron microscopy. Moreover, we observed an irradiation effect that was caused by the microbeam. These results suggest that this photoelectron microspectroscopy system is a powerful tool for studying chemical and electronic states of submicron-area surfaces.

The effects of crystal defects near the surface on the position of surface Fermi level (EFS) are investigated using photoluminescence (PL) measurements and synchrotron radiation photoelectron spectroscopy (SRPES). For the lightly Sidoped GaAs (001) surface, PL measurements reveal that after heating to 500°C a layer with lower PL peak intensities related to gallium vacancies than those of the bulk exists just under the thermal degraded layer. SRPES shows that EFS moves upward to 1.1-1.17 eV above the valence band maximum when this thermal degraded layer is removed by chemical etching. The excess arsenic on the surface, which is formed by rinsing the etched surface with deoxygenated and deionized water, is evaporated by heating in ultra-high vacuum (UHV). After evaporation of excess arsenic on the surface by heating, the etching-depth dependence of EFS for a sample pre-heated in UHV correlates with the existence of this defect concentration layer. These results suggest that the position of EFS for GaAs (001) surface is strongly influenced by crystal defects near the surface.

Deposition of Al and Au was performed on a Se treated GaAs(100) surface. The deposition of Al at low coverages results in a significant reduction in band bending that is interpreted in terms of further passivation of the Se treated GaAs surface. At intermediate coverages, band bending is consistent with what one would expect on the basis of Schottky limit. In this intermediate thickness regime, the formation of metallic Ga resulting from a Ga-Al exchange reaction producing a thermodynamically stable AlxSey interlayer is observed. At higher Al coverages, band bending is increased and is accompanied by Se surface segregation and a band bending which is slightly higher than expected from an ideal Al/GaAs interface. In a manner similar to Al deposition, deposition of Au results in segregation of only one Se species and provides further evidence on the structure of the Se/GaAs surface. Finally, Schottky barrier heights of 0.3 and 0.9 eV were realized for AI/Se/GaAs and Au/Se/GaAs respectively. This result suggests the Se passivated surface provides a wide degree of freedom in the fabrication of GaAs based Schottky barrier diodes.

We investigated the prognostic significance and post-transcriptional acetylation-modification of cortactin (CTTN) via the nucleus accumbens-associated 1 (NACC1)–histone deacetylase 6 (HDAC6) deacetylation system in primary melanomas and melanoma cell lines. Overexpression of CTTN protein was observed in 56 (73%) of 77 stage I–IV melanomas, and was significantly correlated with tumor thickness, lymph node metastasis, distant metastasis, and disease outcome. The patients whose tumors exhibited CTTN overexpression had a poorer outcome than patients without this feature (P=0.028, log-rank test). NACC1 and CTTN proteins, but not HDAC6, were overexpressed in four melanoma cell lines in comparison with a primary culture of normal human epidermal melanocytes. Knockdown of both NACC1 and HDAC6 markedly downregulated the migration activity of all melanoma cell lines (P

Low-energy electron microscopy (LEEM) was used to measure the reflectivity of low-energy electrons from graphitized SiC(0001). The reflectivity shows distinct quantized oscillations as a function of the electron energy and graphite thickness. Conduction bands in thin graphite films form discrete energy levels whose wave vectors are normal to the surface. Resonance of the incident electrons with these quantized conduction band states enhances electrons to transmit through the film into the SiC substrate, resulting in dips in the reflectivity. The dip positions are well explained using tight-binding and first-principles calculations. The graphite thickness distribution can be determined microscopically from LEEM reflectivity measurements., 7 pages, 3 figures

Disseminated intravascular coagulation (DIC) is a very rare complication of pulmonary tuberculosis. We herein describe a case of cavitary tuberculosis complicated with DIC. Rifampin was considered to deteriorate the clinical course of DIC in this case.

Reciprocal activation of prourokinase (pro-u-PA) and plasminogen is an important mechanism in the initiation and propagation of local fibrinolytic activity. We found that glucosyldiacylglycerol (GDG) enhanced the reciprocal activation by 1.5- to 2-fold at 0.7-16 microM, accompanying increased conversions of both zymogens to active two-chain forms. The reciprocal activation system consists of (i) plasminogen activation by pro-u-PA to form plasmin, (ii) pro-u-PA activation by the resulting plasmin to form two-chain u-PA (tcu-PA), and (iii) plasminogen activation by the resulting tcu-PA. Whereas GDG minimally affected steps (ii) and (iii) in isolated systems, it markedly enhanced step (i) in the absence of the conversion of pro-u-PA to tcu-PA. GDG significantly increased the intrinsic fluorescence of pro-u-PA (6.7%), but not that of tcu-PA or plasminogen. The large change in intrinsic fluorescence suggests that GDG selectively affects pro-u-PA to alter its conformation, and this mechanism may account for enhancement of its intrinsic plasminogen activator activity.

A system has been developed for the real-time analysis of surface reactions during molecular beam epitaxial growth which uses photoelectron spectroscopy with VUV light taken from synchrotron radiation. This system consists of a synchrotron radiation beamline and growth/analysis apparatus in which photoelectron spectroscopy is performed with sub-second time resolution. In this system, photoelectron spectra are measured in sequence by a `non-scanning' measurement method that enables the acquisition of snapshot photoelectron spectra using a multi-channel detector. This non-scanning measurement method was enabled by equipping an electric field correction grid. This system was used to monitor the photoelectron spectra of a GaSb(001) surface.

A vacuum ultraviolet beamline with a grazing-incidence constant-deviation-angle monochromator, equipped with a varied-line-spacing plane grating, has been designed for a bending-magnet light source. This type of monochromator has become very popular because of its high resolution, high throughput, simple scanning mechanism and fixed exit slit. To improve the energy resolution for a wide spectral range, Yan & Yagishita [(1995), KEK Report 95-9. KEK, Tsukuba, Ibaraki 305, Japan] proposed eliminating the defocus aberration at two specific energies in the spectral range, and their monochromator successfully achieved higher energy resolution by using an undulator light source. The possibility of applying this method to a bending-magnet beamline was examined and it was found that high performance can be achieved even using a bending-magnet light source with wide emittance. Performance evaluation relating to energy resolution, photon flux and spot size are reported.

深層地下水 (70℃) の流動調査に適したアクチバブルトレーサを選択するため, まず地下約1000mから採取した岩石に対するインジウムとジスプロシウム化合物 (硝酸塩とキレート錯体) の吸着損失をバッチ法とカラム法とで調べた。つぎに, トレーサとしてDyキレート錯塩 (Dy-DTPA) とIn-DTPAを実際の還元井に各1kg投入し, 112mの距離にある生産井においてトレーサを含む熱水の再湧出を観測した。その結果, 11000m3と21000m3揚水したときにDy-DTPAとIn-DTPAはそれぞれ最大濃度として0.9μg/lと0.4μg/lで検出された。これから, In-DTPAのかなりの部分が吸着か化学的な分解により失われた可能性があるが, Dy-DTPAはそのような損失がほとんどなく, 目的の対象に対してトレーサとして有用であることが認められた。

Clay mineralogy, together with silt and sand mineralogy and some chemical and physical characteristics, was investigated for samples from 10 profiles of Red-Yellow Podzolic soils (Inceptisols, Alfisols, and Ultisols) from Korea. The soils were generally strongly acid in reaction, except for those developed on limestone and from cultivated lands. Soil texture varied with profiles and horizons, ranging generally from silty clay to light clay to heavy clay. The silt fraction consisted, in all the profiles, principally of quartz with a small amount of feldspars and layer silicates, and the sand fraction was dominated by quartz and feldspars, with fair amounts of dolomite, micas, rock fragments, iron concretions, or clay aggregates depending on the profiles. Such mineralogical composition of the silt and sand fractions reflected well the Iithological nature of the parent materials or the stage of soil development. Clay mineralogical composition varied from profile to profile, though not very much in the sequen...

A submicrometre-area photoelectron spectroscopy system that uses a multi-layer-coated Schwarzschild objective as the soft X-ray microbeam optics has been developed. The system is located at an undulator beamline (BL-16U) at the Photon Factory in the High Energy Accelerator Research Organization. By knife-edge measurement, the microbeam size was estimated to be 160 nm at the sample position using a 25–75% criterion. Photoelectron spectral measurements revealed that the Fermi edge width was 0.12 eV, which means that the instrumental resolution was 0.05 eV, after removing the natural broadening of the Fermi edge at room temperature. This system offers both high energy resolution and high spatial resolution.