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The finite difference method has adequate accuracy to calculate fully-developed laminar flows in regular cross-sectional domains, but in irregular domains such flows are solved using the finite element method or structured grids. However, it has become apparent that we can use the finite difference method freely even if domains are complex. The non-slip condition on the wall must be imposed. Even in irregular domains, this boundary condition can be introduced indirectly by adding a single procedure to set the boundary condition. The calculations have similar accuracy as in regular domains. The proposed method has a wide range of applications; as a first step, fully-developed laminar flows are investigated in the paper. © 2011 Copyright 2011 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License.

Urashima Y.,Japan National Agricultural Research Center | Sonoda T.,Fukushima Prefecture Government | Fujita Y.,Fukushima Prefecture Government | Uragami A.,National Institute of Vegetable and Tea Science
Microbes and Environments | Year: 2011

Growth inhibition due to continuous cropping of asparagus is a major problem; the yield of asparagus in replanted fields is low compared to that in new fields, and missing plants occur among young seedlings. Although soil-borne disease and allelochemicals are considered to be involved in this effect, this is still controversial. We aimed to develop a technique for the biological field diagnosis of growth inhibition due to continuous cropping. Therefore, in this study, fungal community structure and Fusarium community structure in continuously cropped fields of asparagus were analyzed by polymerase chain reaction/denaturing-gradient gel electrophoresis (PCR-DGGE). Soil samples were collected from the Aizu region of Fukushima Prefecture, Japan. Soil samples were taken from both continuously cropped fields of asparagus with growth inhibition and healthy neighboring fields of asparagus. The soil samples were collected from the fields of 5 sets in 2008 and 4 sets in 2009. We were able to distinguish between pathogenic and non-pathogenic Fusarium by using Alfie1 and Alfie2GC as the second PCR primers and PCR-DGGE. Fungal community structure was not greatly involved in the growth inhibition of asparagus due to continuous cropping. By contrast, the band ratios of Fusarium oxysporum f. sp. asparagi in growth-inhibited fields were higher than those in neighboring healthy fields. In addition, there was a positive correlation between the band ratios of Fusarium oxysporum f. sp. asparagi and the ratios of missing asparagus plants. We showed the potential of biological field diagnosis of growth inhibition due to continuous cropping of asparagus using PCR-DGGE.

Nuimura T.,Nagoya University | Nuimura T.,Chiba Institute of Science | Sakai A.,Nagoya University | Taniguchi K.,Nagoya University | And 16 more authors.
Cryosphere | Year: 2015

We present a new glacier inventory for high-mountain Asia named "Glacier Area Mapping for Discharge from the Asian Mountains" (GAMDAM). Glacier outlines were delineated manually using 356 Landsat ETM+ scenes in 226 path-row sets from the period 1999-2003, in conjunction with a digital elevation model (DEM) and high-resolution Google EarthTM imagery. Geolocations are largely consistent between the Landsat imagery and DEM due to systematic radiometric and geometric corrections made by the United States Geological Survey. We performed repeated delineation tests and peer review of glacier outlines in order to maintain the consistency and quality of the inventory. Our GAMDAM glacier inventory (GGI) includes 87 084 glaciers covering a total area of 91 263 ± 13 689 km2 throughout high-mountain Asia. In the Hindu Kush-Himalaya range, the total glacier area in our inventory is 93% that of the ICIMOD (International Centre for Integrated Mountain Development) inventory. Discrepancies between the two regional data sets are due mainly to the effects of glacier shading. In contrast, our inventory represents significantly less surface area ('24%) than the recent global Randolph Glacier Inventory, version 4.0 (RGI), which includes 119 863 ± 9201 km2 for the entirety of high Asian mountains. Likely causes of this disparity include headwall definition, effects of exclusion of shaded glacier areas, glacier recession since the 1970s, and inclusion of seasonal snow cover in the source data of the RGI, although it is difficult to evaluate such effects quantitatively. Further rigorous peer review of GGI will both improve the quality of glacier inventory in high-mountain Asia and provide new opportunities to study Asian glaciers. © Author(s) 2015. CC Attribution 3.0 License.

Hibino M.,Fukushima Prefecture Government | Matsuzaki K.,Fukushima Prefecture Government | Komai T.,Natural History Museum and Institute
Zootaxa | Year: 2015

Pandalopsis spinosior Hanamura, Kohno & Sakaji, 2000 (Decapoda: Caridea: Pandalidae) was originally described on the basis of material collected in the Urup Strait, South Kurile Islands, but there have been no subsequent records of the species since the original description. The Marine Science Museum, Fukushima Prefecture (Aquamarine Fukushima) has carried out investigations on deep-water animals in the Nemuro Strait, off Shiretoko Peninsula, Hokkaido, Japan, amongst the collections a large, commercially important pandalid shrimp routinely identified with P. coccinata Urita, 1941. Examination of the specimens from the collections, however, resulted in an unexpected identification with P. spinosior, instead of P. coccinata. In this short article, diagnostic characters of P. spinosior are reassessed, and comparison with P. coccinata is made. The validity of P. zarenkovi Ivanov & Sokolov, 2001, for which possible synonymy with P. spinosior was suggested, is maintained for the time being. © 2015 Magnolia Press.

Matsuzaki K.,Fukushima Prefecture Government | Hibino M.,Fukushima Prefecture Government | Komai T.,Natural History Museum and Institute Chiba
Zootaxa | Year: 2015

A new species of the caridean shrimp genus Lebbeus White, 1847 (Thoridae), L. fujimotoi n. sp. is described and illus-trated on the basis of material from the Nemuro Strait, southwestern part of the Sea of Okhotsk, Hokkaido, Japan, at depths of 500-800 m. The new species belongs in the informal species group characterized by the possession of an epipod only on the third maxilliped, containing only L. elegans Komai, Kohtsuka & Hayashi, 2004 among the 65 previously described specific taxa. The elongate and strongly upturned rostrum with more numerous ventral teeth (seven or eight versus one to four) and the presence of a posteroventral tooth on the fourth pleonal pleuron immediately distinguish the new species from L. elegans. Species of Lebbeus reported from the Sea of Okhotsk are briefly overviewed. Copyright © 2015 Magnolia Press.

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