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We present the results of six-epoch Very Long Baseline Array (VLBA) observations of 3C 66A. The high-resolution Very Long Baseline Interferometer (VLBI) maps obtained at multi-frequency (2.3, 8.4, and 22.2 GHz) simultaneously enabled us to identify the brightest compact component with the core. We find that the spectrum of the core can be reasonably fitted by the synchrotron self-absorption model. Our VLBA maps show that the jet of 3C 66A has two bendings at about 1.2 and 4 mas from the core. We also give possible identifications of our jet components with the components in previous VLBA observations by analysing their proper motions. We find consistent differences of the position from the core in one component between different frequencies at six epochs.

We present the catalogs and source counts for the C_90 (reference wavelength of 90 ) and C_160 (170 ) bands, which were extracted from our analysis of an ISO deep far-infrared survey conducted as part of the Japan/UH ISO cosmology project. The total survey area is ~0.9 deg2in two fields within the Lockman Hole. The analysis consists of source extraction using the IRAF DAOPHOT package and simulations carried out by adding artificial sources to the maps to estimate the detection rate, the flux bias, the positional accuracy, and the noise. The flux calibration was performed using the Sb galaxy UGC06009 – the photometric error was estimated to be ~50% at C_90 and ~65% at C_160. The total noise estimated from the simulation is dominated by the confusion noise due to the high source density. The confusion noise is ~20 mJy at C_90 and ~35 mJy at C_160, which is much larger than the instrumental noise which is at the level of a few mJy or less. The catalogs were constructed by selecting 223 C_90 sources and 72 C_160 sources with a Signal to Noise Ratio (SNR) of three or greater. The distribution of the observed associations between C_90 and C_160 sources indicates that the $1 \sigma$positional errors are ~20´´ and ~35´´ at C_90 and C_160, respectively. The corrections for the detection rate and the flux bias are significant for sources fainter than 200 mJy at C_90 and 250 mJy at C_160. Most of the sources detected both at C_90 and C_160 have a F(C_160)/F(C_90) color redder than the Sb galaxy UGC 06009. Such a red color could result from reddening due to the flux bias or a K-correction brightening due to the effect of redshift. Red sources brighter than 200 mJy at C_160 may be very luminous galaxies like Arp 220 at moderate redshift. The source counts are derived by applying the corrections for the detection rate and flux bias. The resultant counts are quite consistent with the constraints derived from the fluctuation analysis performed in Paper II. The C_160 counts are also consistent with the results from the FIRBACK project. Our C_90 survey, which is 2–3 times deeper than those previously published, reveals an upturn in the count slope at around 200 mJy. While recent models give a reasonable fit to the C_160 counts, none of them are successful in accounting for the upturn in the C_90 counts. If the upturn is caused by ultraluminous IR galaxies, their redshifts would need to be at $z \sim 0.5$, implying a major event in galaxy evolution at moderate redshift.

Climate change increases the occurrence of chalky rice (Oryza sativaL.) through frequent extreme weather conditions, such as high temperature and low radiation. The objective of this study was to examine the possibility of developing prediction methods for estimating the occurrence of a major type of chalky rice, the milky‐white rice. The methods evaluated the chalky patterns on the transverse section of premature grains by visual inspection or by employing a newly developed image analyzer. The predicted grain rates of milky‐white rice using the above‐mentioned method(s) as well as two other methods using a grain scanner, were compared with periodically sampled grains approaching maturity under shade treatments at Kagoshima and Fukuoka, Japan. The grain rates predicted using visual inspection and the developed analyzer at 6 to 7 d before maturity (DBM) and 9 to 10 DBM, were positively correlated with the target grain rates of milky‐white rice obtained at maturity; R2was 0.906 (p< 0.01) to 0.964 (p< 0.001), and the RMSE value ranged from 2.00 to 6.10, at both the DBMs. In the methods employing the grain scanner, the correlations between the predicted and target grain rates at the same DBMs were lower; R2was 0.556 (p= 0.054) to 0.777 (p< 0.01), the RMSE value was between 7.86 and 12.03. Thus, the methods using transverse section of premature grains developed in this study could be applied for predicting the occurrence of milky‐white rice a week to 10 DBM. Occurrence of milky‐white rice can be predictable using transverse section of the premature grain.The chalky zone detected inside the transparent area on the transverse section is the indicator.The method is based on the regularity of starch accumulation from center towards peripheral in the grain.This method will contribute to mitigation of grain breakage through postharvest management. Occurrence of milky‐white rice can be predictable using transverse section of the premature grain. The chalky zone detected inside the transparent area on the transverse section is the indicator. The method is based on the regularity of starch accumulation from center towards peripheral in the grain. This method will contribute to mitigation of grain breakage through postharvest management.

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Melanin has been proposed as a virulence factor in Cryptococcus neoformans, but its presence has not been shown unambiguously in vivo. Validated methods used previously to show production of cryptococcal eumelanin pigment in vitro (P. R. Williamson, K. Wakamatsu, and S. Ito, J. Bacteriol. 180:1570-1572, 1998) were used to assess for production of laccase-derived products in mouse brain of the Lacc+ strains, 2E-TUC, H99 (serotype A), and ATCC 34873 (serotype D), and the Lacc- strain, 2E-TU. Pyrrole-2,3, 5-tricarboxylic and pyrrole-2,3-dicarboxylic acid, specific degradation products of catecholamine derivatives such as melanin, were found in all Lacc+ strains, but not in the Lacc- strain, 2E-TU. However, the presence of melanin pigment itself could not be demonstrated in the same cells. Lack of the specific degradation products aminohydroxyphenylalanine and aminohydroxyphenylethylamine in Lacc+ strains upon hydriodic acid hydrolysis showed that pheomelanin was also not produced by the fungus in vivo. These are the first data to support the generation of catecholamine oxidation products by C. neoformans in vivo, but they do not support postenzymatic polymerization of these products to form typical eumelanin, as previously proposed.

We have investigated the relationship in human cultured normal and malignant melanocytes between the accumulation of mRNAs encoding tyrosinase and tyrosinase‐related protein‐1 (TRP‐1), the activity of tyrosinase and the presence of melanin. Tyrosinase mRNA correlates with tyrosinase activity and with the presence of pheomelanin, eumelanin or both melanin types. In contrast TRP‐1 mRNA is only detectable in cells containing eumelanin, which suggests a role for TRP‐1 in the eumelanin synthesis pathway.

To elucidate the mechanism whereby liganded receptor molecules enhance nucleotide exchange of GTP-binding regulatory proteins (G proteins), changes in the secondary structure of the recombinant Gi1 alpha subunit (Gi1alpha) upon binding with receptor mimetics, compound 48/80 and mastoparan, were analyzed by circular dichroism spectroscopy. Compound 48/80 enhanced the initial rate of GTPgammaS binding to soluble Gi1alpha 2.6-fold with an EC50 of 30 microg/ml. With the same EC50, the mimetic decreased the magnitude of ellipticity, which is ascribed to a reduction in alpha helix content of the Gi1alpha by 7%. Likewise, mastoparan also enhanced the rate of GTPgammaS binding by 3.0-fold and decreased the magnitude of ellipticity of Gi1alpha similar to compound 48/80. In corresponding experiments using a K349P-Gi1alpha, a Gi1alpha counterpart of the unc mutant in Gsalpha in which Pro was substituted for Lys349, enhancement of the GTPgammaS binding rate by both activators was quite small. In addition, compound 48/80 showed a negligible effect on the circular dichroism spectrum of the mutant. On the other hand, a proteolytic fragment of Gi1alpha lacking the N-terminal 29 residues was activated and showed decreased ellipticity upon interaction with the compound, as did the wild-type Gi1alpha. Taken together, our results strongly suggest that the activator-induced unwinding of the alpha helix of the G protein alpha subunit is mechanically coupled to the enhanced release of bound GDP from the alpha subunit.

A numerical calculation technique for computing bifurcation values of interconnected dynamical systems is presented. The technique is based on continuation methods in which the bifurcation value of interconnected dynamical systems can be calculated from the bifurcation value of a subsystem using a set of coupled differential equations. As an example, the value of the Hopf bifurcation of an interconnected dynamical system is calculated.

A compilation was made of the total number of globular clusters associated with M 104, M87, and all the members of the Local Croup except for the Magellanic Clouds. We found that the total number of clusters in a galaxy increases approximately linearly as the luminosity of the spheroidal system of a parent galaxy increases, where the spheroidal system means the spheroidal central bulge for the spiral galaxies, or the whole system for elliptical galaxies. Key words: globular clusters-spheroidal central bulge-galaxies

Stellar images around M 104 fainter than a threshold magnitude are concentrated toward the nucleus, thus they are certainly globular clusters associated with M 104. By counting their images, the radial distribution of their projected number density is found to be similar to the luminosity profile of the spheroidal central bulge and can be represented by de Vaucouleurs' "1/4-law". The total number of globular clusters in M 104 is estimated to be (2.0+ i: o) x 10 . Key words: globular clusters- spiral galaxies- spheroidal central bulge

Most of the natural melanin pigments consist of not only indolic eumelanin but also sulfur-containing pheomelanin. Previous methods for spectrophotometric assay of melanins use solubilization in alkaline media; a major disadvantage of these procedures is that they do not distinguish between eumelanin and pheomelanin. A spectrophotometric method for assaying eumelanin in tissue samples is described. Sepia melanin serves as a standard. Hair and melanoma samples were hydrolyzed in hot hydriodic acid, and insoluble eumelanic pigments were solubilized in hot sodium hydroxide in the presence of hydrogen peroxide and analyzed for absorbance at 350 nm (A350). The detection limit of eumelanin was ca. 2 μg. Eumelanins prepared from dopa, 5,6-dihydroxyindole and its carboxy derivative gave similar A350values. Mixed-type melanins prepared from dopa and various ratios of cysteine gave A350values inversely proportional to their sulfur contents. Excellent correlations were observed between A350values and contents of pyrrole-2,3,5-tricarboxylic acid, an oxidation product specific for eumelanin, in hair samples from sheep and humans of various colors and in melanomas and eyes from mice. The present method provides a specific and direct measurement of eumelanin contents in tissue samples.

We have investigated the relationship in human cultured normal and malignant melanocytes between the accumulation of mRNAs encoding tyrosinase and tyrosinase-related protein-1 (TRP-1), the activity of tyrosinase and the presence of melanin. Tyrosinase mRNA correlates with tyrosinase activity and with the presence of pheomelanin, eumelanin or both melanin types. In contrast TRP-1 mRNA is only detectable in cells containing eumelanin, which suggests a role for TRP-1 in the eumelanin synthesis pathway.

Generalized melanosis occurs very rarely as a complication of malignant melanoma, and the pathogenesis of this condition is still unclear. Histological examination of pigmented skin and measurements of the DOPAquinone metabolites 5-S-cysteinyldopa (5-S-CD) and 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI2C) in the patient’s serum and urine were carried out. Histological examination revealed basal hyperpigmentation, discrete melanoma cells and melanophages around the blood vessels and an unusual melanin deposition within collagen bundles in the dermis. The levels of 5-S-CD and 6H5MI2C were dramatically increased both in the patient’s serum and urine. The deposition of DOPAquinone metabolites secreted by the melanoma cells may contribute to the unusual melanin deposition within collagen bundles in the affected dermis.

Okadaic acid is a polyether compound of a C38 fatty acid, isolated from a black sponge, Halichondria okadai. Previous studies showed that okadaic acid is a skin irritant and induces ornithine decarboxylase (OrnDCase; 3-hydroxyl-L-glutamate 1-carboxy-lyase, EC 4.1.1.17) in mouse skin 4 hr after its application to the skin. This induction was strongly inhibited by pretreatment of the skin with 13-cis-retinoic acid. A two-stage carcinogenesis experiment in mouse skin initiated by a single application of 100 micrograms of 7,12-dimethylbenz[a]anthracene (DMBA) and followed by application of 10 micrograms of okadaic acid twice a week revealed that okadaic acid is a potent additional tumor promoter: tumors developed in 93% of the mice treated with DMBA and okadaic acid by week 16. In contrast, tumors were found in only one mouse each in the groups treated with DMBA alone or okadaic acid alone. An average of 2.6 tumors per mouse was found in week 30 in the group treated with DMBA and okadaic acid. Unlike phorbol 12-tetradecanoate 13-acetate (TPA), teleocidin, and aplysiatoxin, okadaic acid did not inhibit the specific binding of [3H]TPA to a mouse skin particulate fraction when added up to 100 microM or activate calcium-activated, phospholipid-dependent protein kinase (protein kinase C) in vitro when added up to 1.2 microM. Therefore, the actions of okadaic acid and phorbol ester may be mediated in different ways. These results show that okadaic acid is a non-TPA-type tumor promoter in mouse skin carcinogenesis.

It is shown that the mean mass density of the earth Galaxy can be expressed by only the tidal radii and the masses of globulars and dwarf spheroidals. The mean mass density law is determined as a function of radius, and used to estimate the mass of the Galaxy. Evidence is also obtained against the existence of a massive halo in the Galaxy, provided the boundaries of globulars and dwarf spheroidals are tidally limited.

A new ring galaxy has been discovered in the halo of a nearby rich cluster of galaxies, Abell 1631. The position of the galaxy is alpha = 12h 48 m 27.1s + or - 0.2s, delta = 14 deg 52 arcmin 00 arcsec + or - 3 arcsec. A bright nucleus having a diameter of 3.5 arcsec is located off-center in the ring. The west edge of the ring is slightly bright, which may be due to the presence of giant H II regions. A companion galaxy about one magnitude fainter than the ring galaxy is located nearly on the minor axis of the ring, separated by 14.5 arcsec from the nucleus. Between them, a barely traceable faint bridge can be seen. If the object is assumed to be a cluster member, its absolute magnitude is -20.0 + or - 0.5 on the scale H = 55 km/s/Mpc. The linear diameter of the ring is about 23 kpc, typical of ring galaxies.

We present initial results of a deep mid-infrared survey conducted in the high galactic latitude field SSA13 with ISO. We have surveyed through the broad band filter LW2 (5-8.5 μm) of the mid-infrared camera ISOCAM to probe the near-infrared light at high redshift. The 80% completeness limit for point sources in the central 6 arcmin2reaches 10 μJy at 6.7 μm. 65 sources are detected down to 6 μJy in 16 arcmin2. The integral galaxy number counts are 1.4 × 104deg-2at 10 μJy with the slope of -1.5. The integrated 6.7 μm light down to 6 μJy is estimated as 0.43 nWm-2sr-1. Our counts are consistent with the results in the HDF and the model prediction based on the Kband local luminosity function. It suggests that the majority of the detected sources are E/S0 galaxies at z>1.

A novel bromine-containing alkaloid, hymenin, has been isolated from the Okinawan marine spongeHymeniacidonsp. as a potent α-adrenoceptor blocking agent and its structure determined to be1on the basis of the spectral data.

The isomeric ratios of the products depend on the reaction time, solvent and the ratio acetylene: Ph3GeH.

The alkynes (I) are coupled with the thiols (II) in the presence of triethylboron to give the 1‐sulfenylalkenes (III).

The acetylenes (I) are coupled with triphenylgermane (II) in the presence of triethylboron to give the alkenylgermanes (III).

A problem for studies of large scale structures in nearby space (cz< 10,000 km s-1) is the presence of the Zone of Avoidance which is so large and wide on the sky that potentially important clusters and voids remain undetected. A prime example was the Ophiuchus cluster discovered by Wakamatsu and Malkan (1981) as a heavily obscured cD cluster close to the Galactic centre region (l= 0·5°, b= +9·5°). It is the second brightest X-ray cluster after Perseus. A hidden galaxy survey was performed by visually searching ESO/SERC Sky Survey (R and J) copy films of the region centred at l= 355°, b= +10° finding more than 4000 galaxies in six fields. Several irregular clusters adjacent to Ophiuchus were found forming a supercluster which may be connected to the Hercules supercluster by a wall structure parallel to the local supergalactic plane (Wakamatsu et al. 1994). In front of this supercluster, an 'Ophiuchus Void' is suggested (cz= 4,500 km s-1). The Ophiuchus supercluster at cz= 8,500 km s-1is similar to the Hercules supercluster (cz= 11,000 km s-1), and extends north toward the latter supercluster.

The structure (I) for the title compound is elucidated on the basis of chemical and spectral evidences.

The title compounds (I) and (II) are identified in the carcinogenic fraction obtained from the title species.

It is shown that the photoexcitation of the electron donor‐acceptor complexes TCNE/(I) leads only to the efficient electrocycloreversions giving (II) without the subsequent isomerization to yield (III).

The bicyclic ketone (Ia) reacts with trimethylchlorosilane (II) after lithiation to give the bridgehead substitution product (Ib).