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971.
Investigations were conducted on the flathead flouder Hippoglossoides dubius to analyze the environmental conditions around the spawning grounds and the maturational status of spawners in the Sea of
Japan off Niigata. In both sexes, larger fish matured earlier than smaller individuals, and participated in breeding from
the early part of the spawning season. Males were always the predominant sex found within the spawning ground, likely because
males spent longer periods in the spawning grounds than females. This finding further suggests that males matured earlier
and maintained sexual activity for longer periods than females within the spawning grounds. Submarine topography and water
temperature were concluded to be important factors affecting the formation of the spawning grounds. The spawning ground was
located within a restricted area where bathymetric lines curve towards a shallow area. Adult fish usually occur in the Japan
Sea Proper Water (<1 °C), but spawners gathered just below the surface mixing layer where water temperature was 5–10°C. Hence,
it was thought that the flounder spawn at the upper tolerable water temperature limit (i.e. the shallowest accessible depth)
to release their offspring into the surface layer. 相似文献
972.
This survey was conducted from 2005 to 2008 regarding the thermal environment of three types of experimental houses—a wood and mud composite wall type (Type WM), a mud wall type (Type M), and an insulated wall type (Type I). To reveal the influence of the wall composition of wooden houses on the indoor thermal environment, each experimental house was constructed on the same site. As a result, under natural indoor air temperatures, the monthly average indoor air temperature level and the time ratio of indoor air temperature surpassing the outdoor air temperature were in the following order: Type I > Type WM > Type M. Type WM exhibited the highest phase shift of air temperature, indicating that the insulation performance and heat capacity affect the phase shift of air temperature. The equalization of indoor air temperature through the suppression of the increase in the indoor air temperature of Type M is likely caused by low insulation performance and large thermal capacity. The time fluctuations in electric consumption by air conditioning and indoor–outdoor air temperature differences of each experimental house over 1 day indicated that a building’s thermal load and the thermal capacity are related. 相似文献
973.
Influence of Hatchery Protocols on Mitochondrial DNA Variation in Japanese Flounder Juveniles 总被引:1,自引:0,他引:1
Takashi Asahida Yumi Shinotsuka Unji Saitoh Yoh Yamashita Hitoshi Ida Ken-Ichi Hayashizaki 《Journal of the World Aquaculture Society》2003,34(2):121-132
The Japanese flounder Paralichthys olivaceus is a commercially important fish that is stocked extensively from hatchery rearing programs in Japan. To examine the genetic variability of hatchery-raised juveniles of the Japanese flounder that are used for stocking into natural waters, we analyzed a portion of the mitochondrial genome. The mtDNA region extending from the 3'half of the cytochrome b gene to the central domain of the control region was PCR amplified and analyzed using 11 restriction endonucleases. We identified 34 polymorphic cleavage sites out of a total of 61 sites, which resulted in 67 different haplotypes in a total of 265 offspring, examined from eight hatchery stocks. Haplotype diversity of offspring at each of the eight hatcheries ranged from 0.49 ± 0.09 (SE) to 0.94 ± 0.03 (SE). Also, we observed 40 polymorphic sites out of a total of 59 sites, which resulted in a total of 50 haplotypes in 60 wild flounder. Haplotype diversity of the wild population was 0.98 ± 0.01 (SE). The use of subcultured fishes as broodstock appears to be one of the most important causes of reduced genetic diversity in hatchery-raised flounder juvenile. Our results suggest that the use of wild fish for broodstock is an effective way to maintain genetic variability in Japanese flounder offspring. 相似文献
974.
Soil erosion in agricultural fields affects not only land productivity but also water environment down stream. Many investigations
have been made for the prediction of soil erosion processes. The Universal Soil Loss Equation (USLE) has been applied broadly
for the prediction of average annual soil loss from upland fields. However, there are few reports concerning the prediction
of nutrient (N, P) losses based on the USLE. Thus, the objective of this study is to propose the prediction equation of nitrogen
and phosphorus losses during soil erosion processes on the basis of the USLE. In order to predict total nitrogen and phosphorus
losses, the coefficients for total nitrogen or phosphorus transfer are derived on the basis of results from experimental field
plots. Three bare-cover USLE plots with different amounts of granular chemical fertilizer were installed in an experimental
upland field. There was a tendency for the coefficient of total nitrogen or phosphorus transfer to increase with the average
concentration of total nitrogen or phosphorus in the soils. It follows that the more granular chemical fertilizer applied
caused a higher coefficient of total nitrogen or phosphorus transfer in the calculations. Moreover, the coefficients in heavily
fertilized plots were higher than 1.0. Through this investigation, it became clear that the nutrient losses during soil erosion
could be predicted on the basis of the coefficient of total nitrogen or phosphorus transfer along with other soil erosion
parameters. 相似文献
975.
Tatsuya Sugawara Ponesakki Ganesan Zhuosi Li Yuki Manabe Takashi Hirata 《Marine drugs》2014,12(6):3660-3668
Siphonaxanthin is a specific keto-carotenoid in green algae whose bio-functional properties are yet to be identified. This review focuses on siphonaxanthin as a bioactive compound and outlines the evidence associated with functionality. Siphonaxanthin has been reported to potently inhibit the viability of human leukemia HL-60 cells via induction of apoptosis. In comparison with fucoxanthin, siphonaxanthin markedly reduced cell viability as early as 6 h after treatment. The cellular uptake of siphonaxanthin was 2-fold higher than fucoxanthin. It has been proposed that siphonaxanthin possesses significant anti-angiogenic activity in studies using human umbilical vein endothelial cells and rat aortic ring. The results of these studies suggested that the anti-angiogenic effect of siphonaxanthin is due to the down-regulation of signal transduction by fibroblast growth factor receptor-1 in vascular endothelial cells. Siphonaxanthin also exhibited inhibitory effects on antigen-induced degranulation of mast cells. These findings open up new avenues for future research on siphonaxanthin as a bioactive compound, and additional investigation, especially in vivo studies, are required to validate these findings. In addition, further studies are needed to determine its bioavailability and metabolic fate. 相似文献
976.
Alinne da Silva Raffaella Rossetto Juliana Bombecini Michel Piemonte Takashi Muraoka 《Journal of plant nutrition》2014,37(8):1227-1236
Vinasse is a liquid residue applied as a fertilizer in sugarcane crops. However, in areas far away from sugarcane mills the cost of the distribution can be very high due, the large volume of water. So, one solution is to concentrate the vinasse by the evaporation process to reduce transport costs. Considering that the nitrogen mineralization kinetics is not known in concentrated vinasse, the objective of this study was to evaluate the net and potential nitrogen mineralization in soil that received vinasse concentrated and not concentrated. The treatments with concentrated vinasse provided the highest values of net mineralization and total nitrogen, which presented significant correlation each other, the same way as the potential mineralization values had a positive correlation with the doses and the amounts of total nitrogen. The total nitrogen values can be used as an index of nitrogen availability in soils that received concentrated vinasse. 相似文献
977.
Norihito Yamauchi Mamoru Satou Jyuichi Shimazu Takashi Shirakawa Seizo Horiuchi 《Journal of General Plant Pathology》2007,73(1):29-34
Race 2 isolates of Fusarium oxysporum f. sp. lactucae have been recognized as biotin auxotrophs and consequently have restricted growth on Puhalla's minimal medium (MM), which
contains no biotin. Biotin-autotrophic isolates were raised from race 2 isolates through cultural mutation that grew as well
on MM as they did on MM supplemented with biotin. These autotrophs were identical to the parental isolates in pathogenicity
on race differential cultivars of lettuce (Patriot, Banchu Red Fire, and Costa Rica No. 4), and thus were designated as race
2. A vegetative compatibility test indicated that the autotrophic isolates fell into the same vegetative compatibility group
as the parents. Culture filtrates of the autotrophs allowed abundant growth of the parental auxotroph on MM, and, through
a competitive enzyme-binding assay, biotin was detected in the culture filtrates. These results suggest that biotin auxotrophy
in the natural race 2 isolates has no direct relation to pathogenicity, qualitatively defined as physiological race, or to
vegetative compatibility. 相似文献
978.
Hiromi?TanabeEmail author Takashi?Nakano Manami?Mimura Yoshiko?Abe Shigeru?Mariko 《Journal of Forest Research》2003,8(4):247-252
We assessed the above- and below-ground biomass and net primary production (NPP) in a mature (85-year-old) Pinus densiflora forest established on a lava surface of Mt. Fuji in central Japan. The nitrogen (N) concentration of the forest soil was low (1.25%), and the mean soil carbon/nitrogen (C/N) ratio was 34.2; therefore, both plants and microorganisms would compete for N in our research forest. The total biomass was 192.62Mgha–1, of which 67.28% was in the stems and 25.71% was in the roots. The fine-root biomass was 1.12% of the total biomass. The total NPP of the forest reached 11.89Mgha–1 year–1, which fell within the values reported for other cool temperate P. densiflora forests established on non-volcanic-related substrata. The below-ground production was about 39% of the total NPP; the value was relatively small under the conditions of low total N concentration and high soil C/N ratio. Our study suggested that P. densiflora could recruit and grow on geologically new substrata without increasing the allocation of its annual carbon budget to below-ground organs (i.e., roots). 相似文献
979.
980.