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71.
Urbanization is expanding in and around small to medium-sized cities as well as in large cities, and the expansion includes low-lying areas where the flood risk is high. Flood risk in small watersheds has been evaluated using precise mathematical models. However, these models cannot be applied to larger basins due to the complexity of data collection and analysis. As a result, quantitative evaluations of flood risk at macro scales and the flood-prevention function of paddies around urban areas have not been made. This paper proposes a method and an index that can be used to evaluate the flood-prevention function of paddies on a regional scale. In addition, the use of this system for basin-wide management is illustrated by an example for the Kinu and Kokai rivers, which are tributaries of the Tone River of Japan. The applicability of the approach is evaluated using data from a major flood that occurred in the study area. 相似文献
72.
Naoki Tani Hiroshi Yoshimaru Takayuki Kawahara Yoshio Hoshi Fuyuo Nobushima Takaya Yasui 《BMC ecology》2006,6(1):14-13
Background
Morus boninensis, is an endemic plant of the Bonin (Ogasawara) Islands of Japan and is categorized as "critically endangered" in the Japanese red data book. However, little information is available about its ecological, evolutionary and genetic status, despite the urgent need for guidelines for the conservation of the species. Therefore, we adopted Moritz's MU concept, based on the species' current genetic structure, to define management units and to select mother tree candidates for seed orchards. 相似文献73.
Sonnenberg GF Monticelli LA Alenghat T Fung TC Hutnick NA Kunisawa J Shibata N Grunberg S Sinha R Zahm AM Tardif MR Sathaliyawala T Kubota M Farber DL Collman RG Shaked A Fouser LA Weiner DB Tessier PA Friedman JR Kiyono H Bushman FD Chang KM Artis D 《Science (New York, N.Y.)》2012,336(6086):1321-1325
The mammalian intestinal tract is colonized by trillions of beneficial commensal bacteria that are anatomically restricted to specific niches. However, the mechanisms that regulate anatomical containment remain unclear. Here, we show that interleukin-22 (IL-22)-producing innate lymphoid cells (ILCs) are present in intestinal tissues of healthy mammals. Depletion of ILCs resulted in peripheral dissemination of commensal bacteria and systemic inflammation, which was prevented by administration of IL-22. Disseminating bacteria were identified as Alcaligenes species originating from host lymphoid tissues. Alcaligenes was sufficient to promote systemic inflammation after ILC depletion in mice, and Alcaligenes-specific systemic immune responses were associated with Crohn's disease and progressive hepatitis C virus infection in patients. Collectively, these data indicate that ILCs regulate selective containment of lymphoid-resident bacteria to prevent systemic inflammation associated with chronic diseases. 相似文献
74.
Matsumoto Y Nakatsuji S Kuga K Karaki Y Horie N Shimura Y Sakakibara T Nevidomskyy AH Coleman P 《Science (New York, N.Y.)》2011,331(6015):316-319
Fermi liquid theory, the standard theory of metals, has been challenged by a number of observations of anomalous metallic behavior found in the vicinity of a quantum phase transition. The breakdown of the Fermi liquid is accomplished by fine-tuning the material to a quantum critical point by using a control parameter such as the magnetic field, pressure, or chemical composition. Our high-precision magnetization measurements of the ultrapure f-electron-based superconductor β-YbAlB(4) demonstrate a scaling of its free energy that is indicative of zero-field quantum criticality without tuning in a metal. The breakdown of Fermi liquid behavior takes place in a mixed-valence state, which is in sharp contrast with other known examples of quantum critical f-electron systems that are magnetic Kondo lattice systems with integral valence. 相似文献
75.
The first stars fundamentally transformed the early universe by emitting the first light and by producing the first heavy elements. These effects were predetermined by the mass distribution of the first stars, which is thought to have been fixed by a complex interplay of gas accretion and protostellar radiation. We performed radiation-hydrodynamics simulations that followed the growth of a primordial protostar through to the early stages as a star with thermonuclear burning. The circumstellar accretion disk was evaporated by ultraviolet radiation from the star when its mass was 43 times that of the Sun. Such massive primordial stars, in contrast to the often-postulated extremely massive stars, may help explain the fact that there are no signatures of the pair-instability supernovae in abundance patterns of metal-poor stars in our galaxy. 相似文献
76.
Abe S Mukai T Hirata N Barnouin-Jha OS Cheng AF Demura H Gaskell RW Hashimoto T Hiraoka K Honda T Kubota T Matsuoka M Mizuno T Nakamura R Scheeres DJ Yoshikawa M 《Science (New York, N.Y.)》2006,312(5778):1344-1347
The ranging instrument aboard the Hayabusa spacecraft measured the surface topography of asteroid 25143 Itokawa and its mass. A typical rough area is similar in roughness to debris located on the interior wall of a large crater on asteroid 433 Eros, which suggests a surface structure on Itokawa similar to crater ejecta on Eros. The mass of Itokawa was estimated as (3.58 +/- 0.18) x 10(10) kilograms, implying a bulk density of (1.95 +/- 0.14) grams per cubic centimeter for a volume of (1.84 +/- 0.09) x 10(7) cubic meters and a bulk porosity of approximately 40%, which is similar to that of angular sands, when assuming an LL (low iron chondritic) meteorite composition. Combined with surface observations, these data indicate that Itokawa is the first subkilometer-sized small asteroid showing a rubble-pile body rather than a solid monolithic asteroid. 相似文献
77.
78.
Expression of HSP70 in response to heat-shock and its cDNA cloning from Mediterranean blue mussel 总被引:1,自引:0,他引:1
Haruhiko?ToyoharaEmail author Masatomi?Hosoi Isao?Hayashi Satoshi?Kubota Hisashi?Hashimoto Yoshihiro?Yokoyama 《Fisheries Science》2005,71(2):327-332
Expression of HSP70 in response to heat-shock was investigated at the protein and mRNA levels in Mediterranean blue mussel.
Western and Northern blot analyses revealed that HSP70 was expressed following heat-shock in the mantle at both protein and
mRNA levels, suggesting that gene expression of HSP70 is implicated in the cellular response to heat-shock stress in mussel.
It was then attempted to clone HSP70 cDNA in order to determine the primary structure of mussel HSP70. As a result, two full-length
cDNA encoding HSP70 were isolated from a cDNA library prepared from the heat-shocked mantle. The isolated cDNA consist of
single open reading frames of 2067 bp and 1911 bp which encode proteins of 689 amino acids and 637 amino acids, respectively.
Both HSP70 cDNA encode an ATPase do main, and a substrate-binding do main in addition to a Glu-Glu-Val-Asp (EEVD) peptide
motif that is specific for cytosolic HSP70. These findings suggest that the cDNA clones obtained in the present study encode
cytosolic HSP70. 相似文献
79.
80.
Improvement in recruitment of Japanese sardine with delays of the spring phytoplankton bloom in the Sea of Japan 下载免费PDF全文
Taketoshi Kodama Taku Wagawa Seiji Ohshimo Haruyuki Morimoto Naoki Iguchi Ken‐Ichi Fukudome Tsuneo Goto Motomitsu Takahashi Tohya Yasuda 《Fisheries Oceanography》2018,27(4):289-301
To evaluate the impact of temporal variation of primary productivity on the recruitment of Japanese sardine (Sardinops melanostictus) in the Sea of Japan, the phenology of sea surface phytoplankton abundance was estimated from 8 day multiple satellite (SeaWiFS, MODIS‐Aqua, MERIS, and VIIRS) derived sea surface chlorophyll (SSChl) a concentrations from January 1998 to December 2015. Because relationships between SSChl a and in situ chlorophyll a concentrations were significantly different among periods based on the satellite combinations used, maximum and minimum SSChl a concentrations of 1 year were relativized as 1 and 0, respectively. Spatio‐temporal variation of relativized SSChl a concentrations was determined by using empirical orthogonal function (EOF) analysis. Scores in the first EOF mode denoted the basin‐scale variations of SSChl a concentrations in the Sea of Japan, and the major peak from the end of February to the end of May displayed the spring bloom. The logarithm of recruitment per spawner (LNRPS) for sardine was positively affected by delays in the start and end dates of the spring phytoplankton bloom. The delay of the date of the lowest sea surface temperature contributed to the delay of the end of the spring bloom during the period 1998–2015 and elevated the LNRPS during the period 1982–2015. Sardine spawns in the southern Sea of Japan from April to May, hence, delays of the spring bloom prolonged its overlap with sardine larval periods, and thus improved the recruitment of Japanese sardine in the Sea of Japan. 相似文献