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OPC model calibration techniques that use SEM contours are a major reason for the modern day improved fitting efficiency in complex mask design compared to conventional CD-based calibration. However, contour-based calibration has a high computational cost and requires a lot of memory. To overcome this problem, in conventional contour-based calibration, the SEM contour is sampled uniformly at intervals of several nanometers. However, such sparse uniform sampling significantly increases deviations from real CD values, which are measured by CD-SEM. We also have to consider the shape errors of 2D patterns. In general, the calibration of 2D patterns requires higher frequency sampling of the SEM contour than 1D patterns do. To achieve accurate calibration results, and while considering the varied shapes of calibration patterns, it is necessary to set precise sampling intervals of the SEM contour. In response to these problems, we have developed a SEM contour sampling technique in which contours are sampled at a non-uniform rate with arbitrary mask shapes within the allowable sampling error. Experimental results showed that the sampling error rate was decreased to sub-nm when we reduced the number of contour points.

Recently, optical proximity correction model calibration techniques that use SEM contours have enabled possibly significant improvements in complex mask design. However, compared to conventional CD-based calibration, contour-based calibration results in increased errors in 1D features. In fact, our research shows that there is a ~1-nm gap, which we call "CD-gap," between CD measurements directly calculated from a SEM image and CD measurements calculated from SEM contours. To achieve accurate calibration, SEM contours must match the corresponding CD measurements. We have developed a CD-gap-free contour extraction technique in response to this problem. In our technique, a mask edge is classified into shape structures and an optimized SEM contour extraction method is prepared for each shape structure to reduce the CD-gap. Experimental results show that the CD-gap can be decreased to sub-nm, which clearly demonstrates the potential of our proposed technique to play a vital role in the lithography process.

Inhalation of asbestos increases the risk of lung cancer and pulmonary fibrosis. It is difficult to directly assess the distribution and content of inhaled particles in lung tissue sections. The purpose of this study is to employ an in-air micro particle induced X-ray emission (in-air micro-PIXE) system for assessment of the spatial distribution and content of asbestos and other metals in lung tissue. A proton ion-microbeam from this system was applied to irradiate lung tissue of patients with or without asbestosis, tumor tissue from both groups, and asbestos fibers (in vitro). The content of each element composing asbestos and those of other metals were calculated and their distribution was assessed from the characteristic X-ray pattern for each element obtained after irradiation. This in-air micro-PIXE system could identify the location of asbestos bodies composed of Si, Mg, and Fe in lung tissue sections. Macrophage and lymphocytes accumulated in that area. This new system also revealed deposits of titanium, nickel, and cobalt in the lung tissues, in addition to asbestos bodies. The Si and Fe content were higher in lungs with asbestosis than in lungs without asbestosis or in tumor tissue. Analysis of asbestos fibers composed of chrysotile, crocidolite, and amosite showed that the ratios of Si, Fe, and Mg corresponded with those for the chemical structures. In-air micro-PIXE analysis is useful for assessing the distribution and quantities of asbestos bodies and also other metals in lung tissue comparing to immune-related cell localizations, and is also useful for analysis of standard asbestos fibers.

A new ²JC,H index method is described for identification of aldohexopyranose. This method is based on a fact that ²JC,H values reflect the stereochemistry for glycol connectivity. Based on the observed ²JC,H values for galactose, glucose, and mannose, ²JC,H profiles for other aldohexopyranoses are proposed. A combination of ²JC,H values was found to be useful for identification of aldohexopyranosyl residues in glycans.

Collagenase was injected into the Achilles tendon of both hind legs of 10 clinically normal adult male New Zealand white rabbits. One month after induction of the injury, beta-aminoproprionitrile (BAPN) or hyaluronic acid (HA) was injected into the tendon core of the right hind leg of each rabbit, the left hind leg being left untreated. The treatment effects were evaluated by electron microscopy and analysis of the glycosaminoglycan (GAG) content of samples at 2 and 6 months post-treatment. At 2 months, collagen fibrils in tendons from both hind legs were relatively small in diameter, irregularly arranged, and interspersed with abundant active tenocytes as compared with those in normal tendon uninjured by collagenase. In the matrix, the amount of HA increased, but chondroitin-6-sulphate was eliminated. At 6 months, BAPN-treated tendons had small-diameter, regularly arranged collagen fibrils. HA-treated tendons, on the other hand, had large diameters, as well as regularly arranged collagen fibrils by comparison with non-treated tendon. The results suggest that HA, unlike BAPN, promoted healing.

Toll-like receptor 4 (TLR4) recognizes lipopolysaccharide (LPS). MD-2 is associated with TLR4 and imparts LPS responsiveness to it. Little is known, however, as to whether MD-2 directly regulates LPS recognition by TLR4. To address the issue, we took advantage of a species-specific pharmacology of lipid IVa, an analogue of lipid A. Lipid IVa acted agonistically on mouse (m) TLR4/MD-2 but not on human (h) TLR4/MD-2. Lipid IVa antagonized the agonistic effect of lipid A on hTLR4/MD-2. We examined the chimeric complex consisting of mTLR4 and hMD-2 to ask whether species specificity is conferred by TLR4 or MD-2. hMD-2 was clearly distinct from mMD-2 in the way of influencing LPS recognition by mTLR4. hMD-2 conferred on mTLR4 responsiveness to lipid A but not to lipid IVa. Moreover, lipid IVa acted as a lipid A antagonist on mTLR4 that is associated with hMD-2. Collectively, MD-2 directly influences the fine specificity of TLR4.

In the rf-produced plasma, it will be a possible mechanism for the density clamping that the eigenmodes are formed in the axial direction. The higher frequency waves are effective for the higher density plasma production. On the conditions of such a saturation region, we observed clear increase of the density by using fast Alfvén wave with a frequency of tenth cyclotron higher harmonics at the midplane of the central cell. The increasing rate depends on the rf power. An increase of high energy ions is observed with the high frequency wave injection.

The generation of superbase sites by doped alkali metals (Li, Na, and K) on alkaline earth metal oxides (MgO, CaO, SrO, and BaO) has been examined. In catalytic activity for the double bond migration of 4,4-dimethyl-1-pentene and 2,3-dimethyl-1-butene, a large increase in the generation of superbase sites was observed with Na- and K-doped MgO, owing to an electron, or paired electrons, being trapped. The increase in base-catalytic activity was very small for the other materials. The spin concentration of NO2^2- radicals, formed by the selective adsorption of NO on strong base sites, was determined using ESR. The results are well explained by an increase in site generation. When the ionic radius of the alkali metal is smaller than that of the oxide cation, the alkali cation adsorbs onto the superbase sites, which are activated by trapped electron(s). The adsorption of small alkali cations interferes with the electrical inductive effect. In the cases of Na- and K-doping on MgO, the adsorption of the alkali cations on the superbase site resulted in an unstable state, due to insufficient area for their adsorption. As a result, the alkali cations migrated, leading to an increase in site generation. The ratio of the ionic radii of the alkali metal/alkaline earth metal must be 1.46 or larger for the generation of superbase sites.

The dorsocaudal extremities of the caudal lobes of the lungs of racehorses are vulnerable to exercise-induced pulmonary haemorrhage (EIPH). The morphology of the lungs at these sites was studied in 13 Thoroughbred horses aged 18 to 22 months. These animals, which had been performing low-intensity exercise on a track at maximum running speeds of approximately 5–8·5 metres/second (m/s), were withdrawn from the racehorse training programme for reasons of unsuitability. Lung lesions observed in the dorsocaudal lung extremities in 10 of the 13 horses were not found in the craniodorsal or cranioventral portions of the lungs. The lesions, which resembled those previously found in Thoroughbred racehorses aged 5 to 11 years with a history of EIPH, were of two main types, namely, multifocal bronchiolar distortion and alveolar epithelialization. EIPH lesions were found only in horses that had been trained at maximum speeds greater than approximately 7·0 m/s. It would seem, therefore, that exercise intensity is an important factor in the pathogenesis of EIPH and that running speeds greater than approximately 7·0 m/s may be sufficient to generate the pulmonary vascular pressures necessary to cause EIPH lesions in young Thoroughbreds.

Planar technology has been used to make a microlens array monolithically. By selectively diffusing a dopant into the planar substrate a distributed-index planar microlens has been realized. The monomer exchange technique for the plastic substrate and ion exchange and electromigration techniques for the glass substrate are used. In particular a 2-D planar microlens array was fabricated in a glass substrate. Each microlens was 1.2 mm in diameter and the focal length was 9.4 mm. The focused spot of the collimated He–Ne laser beam was as small as 17 μm?.

A series of acyclic nucleosides with two hydroxymethyl groups mimicking the 3‘- and 5‘-hydroxyl groups of the 2‘-deoxyribose moiety were prepared and evaluated for their antiherpetic activity. Among those, 9-[[cis-1‘,2‘-bis(hydroxymethyl)cycloprop-1‘-yl]methyl]guanine (3) showed extremely potent antiviral activity against herpes simplex virus type-1 (HSV-1) with good selectivity. Both enantiomers of 3 were synthesized starting from chiral epichlorohydrins, and only one of the enantiomers with 1‘S,2‘R-configuration (3a) exhibited strong antiherpetic activity (IC50 of 0.020 μg/mL against HSV-1 Tomioka vs 0.81 μg/mL for acyclovir). Enantiomer 3a was also more inhibitory than acyclovir against varicella-zoster virus (VZV) but ineffective against human immunodeficiency virus (HIV). Compound 3a is phosphorylated by HSV-1 thymidine kinase (TK) very efficiently. The relationship between conformation and antiherpetic activity in this series of compounds is discussed.

K18 is an anticancer drug for oral administration comprising about five molecules of melphalan, an alkylating drug, covalently bonded to human immunoglobulin G. This study measured the in vitroantitumour activity of K18, melphalan and immunoglobulin G on human myeloma cells (RPMI-8226) and the in vivoantitumour effects of K18 and melphalan in BALB/c nude mice bearing human lung cancer cells (LC-10). The relative tumour-inhibitory effect, in vitro, was found to be: immunoglobulin G

The instability properties of weakly nonlinear wave packets show a strong directional dependence. The presence of shear is found to enhance the importance of three dimensional effects.