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Etching characteristics of various resins by a vacuum ultraviolet (VUV, =172 nm) light have been examined under conditions of exposure time, substrate temperature, radiation distance and ambient oxygen concentration. The VUV light have used to clean the imprinted molds which are contaminated by organic substances such as ultraviolet-resins through many times of imprinting processes, and it has revealed that the VUV light has effectively regenerated the contaminated molds manufactured by quartz, silicon-carbide and nickel.

Substantial amounts of mercury are usually present in tuna muscle, with levels in excess of 10 times the standard safety value present in some individuals. Inspection of individual fish for mercury content would be desirable but may not be cost-effective. In this study, we tried to establish a low-cost system for checking the mercury content of tuna by using a tail muscle that is usually discarded. The samples used in this experiment were bluefin tuna, cultured in the Fisheries Laboratory of Kinki University (Oshima Experimental Station, Wakayama, Japan). They were raised from eggs spawned in 2002. Ninety-eight individuals, weighing 22.3 to 61.6 kg, were selected between December 2004 and November 2005. In nine individuals, the mercury content of the tail was compared with that of the whole body. The total mercury level was measured using the reduction vaporizing atomic absorption method after acid digestion. Except for the front of the abdomen, where the mercury content was lower (0.490 ppm), the mercury content of other parts of the fish did not differ from that of the tail muscle (0.631 ppm). Therefore, the overall mercury concentration in bluefin tuna could be estimated to be almost the same and/or lower than that of the tail muscle. On the basis of these results, for 1 year we investigated the quantity of mercury in full-cycle cultured bluefin tuna that were shipped. The mercury concentration showed no increase irrespective of increases of body weight.

A two dimensional (2D) GaAs hole array with a high aspect ratio was successfully fabricated by dry etching techniques using a highly ordered alumina membrane as a mask. The reflection spectra of the GaAs hole array shows characteristics of the photonic bandgap (PBG) calculated by using the 2D triangular lattice structure. Various defect lines were formed etching in the GaAs hole array using focused ion beam. The defect-type PBG waveguide was experimentally demonstrated.

Disposition of [125I]rHu-TNF was elucidated in BALB/c mice bearing Meth A fibrosarcoma 7 days after transplantation. Afteri.v. administration, [125I]rHu-TNF measured by radioactivity and immunoreactivity biphasically decreased in plasma. Tumor level of [125I]rHu-TNF was the maximum at 1 h, then decreased and finally remained essentially constant. After i.t. administration, plasma level reached the maximum at 1 h. Tumor level decreased quickly and then became essentially constant. [125I]rHu-TNF was suggested to be degraded to small fragments in the tumor. Significant distribution of [125I]rHu-TNF was found in the kidney, lung, liver and tumor. Most tissue levels decreased with time in parallel with plasma levels. [125I]rHu-TNF radioactivity was found in proximal convoluted tubules of kidney and in those areas of tumor consisting of degenerating cells with pyknotic nuclei. Urine contained most of administered radioactivity, which being neither immunoreactive nor protein-bound.

A direct radioimmunoassay for the accurate determination of haloperidol in human serum has been developed. Based on recent information about the metabolism of haloperidol, a new haloperidol hapten, in which a (3-carboxypropionyl)methylamino group was attached as a bridge in the place of fluorine atom, was synthesized and coupled to bovine serum albumin through the bridge to provide a new immunogen. Guinea pigs were used for the immunization. Since the antisera obtained by the new immunogen still cross reacted >10% with reduced haloperidol, the immunological tolerance to reduced haloperidol was induced by administration of a copolymer of D-glutamic acid and D-lysine linked with reduced haloperidol. This gave an antiserum in guinea pigs which was highly specific for unchanged haloperidol with negligible cross reactivity (≤1.0%) to any haloperidol metabolites including the newly found ones. With the newly developed antiserum and [3H]haloperidol, serum haloperidol levels can be determined over the concentration range from 0.3 to 20 ng/mL, using 0.1mL of human serum, without an extraction procedure.

Through-hole diamond membranes with submicrometer-sized pores were fabricated by oxygen plasma etching through an anodic porous alumina mask. Polished polycrystalline diamond film (3 um thick) was covered with the porous alumina mask and was etched for about 10 min. The resulting diamond membrane after separating from Si had a pore size of about 300 nm diam and a pore density of This technique is simple and allows the controlled preparation of through-hole diamond membranes by varying the dimensions of the alumina mask. These membranes are useful for several applications, including filtration and flow-through electrolysis. (c) 2001 The Electrochemical Society. All rights reserved.

Introduction:Recent trials demonstrated favorable effects of statins on the clinical prognosis, partly through anti-inflammatory properties, in patients with coronary artery disease. However, this favorable effect has not been fully verified in patients with peripheral arterial disease (PAD). We hypothesized that statins exert different prognostic effects depending on the degrees of inflammation at the time of endovascular therapy (EVT).Methods:This study initially included 628 consecutive PAD patients who underwent EVT. After the exclusion of patients without information of C-reactive protein (CRP) at the time of index EVT, 560 patients including 285 statin users and 275 statin non-users were ultimately analyzed. The patient enrolled were divided into 4 categories depending on CRP level at the time of EVT; Low-CRP (<0.1 mg/dL), Intermediate-low-CRP (0.1-0.3 mg/dL), Intermediate-High-CRP (0.3-1.0 mg/dL), and High-CRP (>1.0 mg/dL). A composite of death and major amputation as the primary endpoint of this study was retrospectively compared between statin users and non-users in each CRP category.Results:The composite endpoint occurred in 124 patients during the observation period. Overall, statin users had a significantly lower event rate than non-users (Log-rank test: P=0.002). However, there were no significant difference in the event rates between statin users and non-users in the Low-, Intermediate-Low, and Intermediate-High-CRP categories. Only in the High-CRP category, statin users showed a significantly lower event rate than non-users (P=0.002, Figures). Multivariate Cox regression analysis revealed that statin use was independently associated with the primary endpoint (adjusted hazard ratio: 0.28 [95% confidence interval: 0.14-0.55]), even after the adjustment of covariants.Conclusion:Statins may exert a favorable prognostic effect in PAD patients with highly elevated CRP, but not in those with low to moderate CRP level.

Highly ordered arrays of diamond cylinders with square and triangular cross sections were prepared by CVD synthesis using anodic porous alumina templates with modified pore shapes. The CVD synthesis of diamond was carried out using a microwave enhanced CVD apparatus using alumina templates. By removing the alumina template in concentrated phosphoric acid, an ordered array of cylinders with a uniform size and shape was obtained. The obtained diamond cylinders could be isolated, and yielded the shape- and size-controlled diamond particles.

The anodic sensitized photocurrent at a SnO2electrode in contact with a dye-containing acetonitrile-water mixed electrolyte solution depends remarkably on the solvent composition, due to a change in the adsorption behavior of the dye.

Two-dimensional (2D) photonic crystals were fabricated using anodic porous alumina with a highly ordered air-hole array of triangular lattice with a high aspect ratio of over 200. The transmission properties of the obtained ordered air-hole array in the alumina matrix exhibited a stop band in the spectrum which corresponds to the band gap in 2D photonic crystals.

An ordered array of concaves of nanometer-scale dimensions was fabricated by a direct molding process on an InP single crystal using a SiC master mold. The obtained array of concaves could be applied for the preparation of an ordered textured surface of InP by a post-etching treatment. The treatment in hydrofluoric acid (HF) solution generated a highly ordered and textured surface composed of uniform pyramidal or triangular pits. The mold could be used repeatedly, and this method enables simple maskless patterning of semiconductor single crystals.

Nanoscale pit patterns were formed on a polycarbonate substrate surface, which is commonly used for compact disks, by direct nanoprinting. Pit patterns with 100, 70, and 63 nm pitches were imprinted on the disk surface using a SiC mold with a nanostructure projection pattern. These pitches correspond to the the storage densities of 75, 150, and 185 Gbit/in2. We evaluated the mold-holding temperature and press-pressure dependence of the pit depth. We also evaluated the press-time dependence. With a relatively low press-pressure of 1.3 kg/mm2at room temperature, a 100-nm-pitch pit pattern with a pit depth of over 40 nm was fabricated using a mold with a projection height of 60 nm.

Two-dimensional (2D) photonic crystals in the visible wavelength region were fabricated using anodic porous alumina with a highly ordered hole array configuration. The transmission properties of an ordered triangular array of an air cylinders with high aspect ratio in alumina matrix showed a stop band in the spectrum which corresponds to the band gap in the 2D photonic crystals.

Two surface-grating distributed Bragg reflector (DBR) lasers, one using a 1.55-µm-wavelength InP-based material system and one using a 0.98-µm-wavelength GaAs/AlGaAs material system, were made using the same reactive beam etching technique following single-step growth of the layer structure for the lasers. A 800-nm-deep grooved grating with a 240 nm period for 1.55-µm-wavelength first-order diffraction and one with a 150 nm period for 0.98-µm-wavelength first-order diffraction were formed using electron-beam lithography and Br2-N2mixed-gas reactive beam etching. Single-longitudinal-mode operation with a side-mode suppression ratio of over 27 dB was obtained for both lasers; the output power was more than 15 mW for the 0.98-µm one. Between 15 and 55°C, the measured temperature dependence of the lasing wavelength for both lasers was about 0.1 nm/°C, which is one-fifth of the dependence of a Fabry-Perot-type laser. The performance of these lasers indicates the wide applicability of the present etching technique to the fabrication of various wavelength-selective devices.

Highly ordered anodic porous alumina was used as a mask for a reactive beam etching (RBE) to transform the nanochannel pattern into III-V semiconductors. The alumina mask showed high tolerance to RBE using a Br2/N2mixed gas system. GaAs and InP nanohole arrays with a high aspect ratio and with diameter uniformity of 2%, which was as good as that of the alumina mask, were obtained.

In0.52Al0.48As and In0.53Ga0.47As/In0.52Al0.48As quantum well (QW) structures were grown on (111)B InP substrates by molecular beam epitaxy, and their optical and electrical properties were studied. The photoluminescence (PL) spectrum and electron mobility of the InAlAs layers grown on the (111)B InP substrates were found to have a remarkable dependence on the V/III ratio and the growth temperature. It was found that the PL peak energy of the InGaAs/InAlAs QWs grown under optimized conditions on the (111)B InP substrates shows a remarkable red shift compared to that grown on the (100) InP substrates. An atomic force microscopy observation revealed that the observed red shift for the (111)B QW is induced by a large surface step-bunching.

Modulated light spectra are measured in long-wavelength InGaAs/InAlAs multiple-quantum-well intensity modulators under 990 MHz, large signal modulation. The linewidth broadening factor, ?, is determined from the relation between the intensity modulation index and the sideband strength, relative to the carrier. The minimum ? value is estimated to be 0.60, which is less than that reported in a bulk Franz-Keldysh modulator.

A non-destructive characterization method for epitaxial wafers of vertical-cavity surface-emitting laser (VCSEL) before device processing, and a way for reproducible fabrication of the distributed Bragg reflector (DBR) using this method, are discussed. The DBR, active layer, and cavity length are successfully characterized by using YAG-laser-excited PL measurement and reflectivity-spectrum measurement. For a buried-heterostructure VCSEL, cavity length is evaluated by using a newly assembled small-area-spectral-reflectance measurement system. It is also shown that the cavity length can be tuned by using chemical etching.

The synchrotron radiation lithography process of grating fabrication for distributed feedback (DFB) laser diodes is described. By finely controlling the field size in electron beam writing of the X-ray mask, the grating period can be arbitrarily varied with an accuracy of less than 0.1 nm . Gratings of 0.24-µm period with a ?/4 shift are formed in the Ta absorber X-ray mask, and transferred to the laser substrate by SR exposure. This process is successfully applied to the fabrication of 20-wave-length DFB-LD arrays.

We report, for the first time, a quantitative study on the size fluctuation in e-beam patterned quantum wire structures using atomic force microscopy. By numerically treating the high resolution three-dimensional data obtained with an atomic force microscope, we determine the average wire width and evaluate standard deviations of wire widths. Using these data, we investigate the intra and interwire fluctuations separately. Results show that intrawire fluctuation is greatly reduced by reverse-mesa etching but that the interwire fluctuation remains. This shows that atomic force microscopy is a very powerful tool for the investigation of semiconductor multi-dimensional quantum confined structures.

A large energy shift of excitonic absorption peaks in quaternary InGaAlAs quantum wells operating in the 1.5 µm wavelength region has been demonstrated in a waveguide configuration. Shifts of up to 30 meV (600 Å) and 17 meV (270 Å) have been achieved for the electron-to-heavy-hole and the electron-to-light-hole exciton absorption peaks, respectively. These shifts were obtained using a reverse bias of 6 V and without causing large broadening of exciton features. These values agree well with the calculated values.

The Metalorganic Molecular Beam Epitaxy (Chemical Beam Epitaxy) technique was used to make active layers for Distributed Feed Back (DFB) lasers. Typical characteristics of these lasers-for example a threshold current of 6 mA and a slope efficiency of 0.3 mW/mA per facet-reflect the high homogeneity and high uniformity of the grown layers. The values referred here are the best ever reported for a CBE-grown active layer.