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排序方式: 共有349条查询结果,搜索用时 31 毫秒
51.
Hidekatsu Yamazaki Wataru Aoyama Eiji Masunaga Mamoru Tanaka 《Aquaculture Research》2019,50(4):1107-1116
A field campaign was conducted around salmon cages, using a combination of a towed ADCP and a free‐fall multi‐parameter profiler, in order to investigate flow structures and the possible distribution of effluent materials. Two transect observations showed that hydrographic conditions changed dramatically within 5 days, from highly stratified open water conditions to weak stratification. Three‐dimensional observation revealed that flow was blocked behind the cages and that the blockage was reduced as the distance from the cages increased. The flow speed was positively correlated with the intensity of the backscattering signal. The R2 value was high immediately behind the cages and decreased with distance from the cages. The flow time series behind the cages exhibited a k–2 power law spectrum that was consistent with a typical internal wave spectrum. This suggests that eddies shed from the cages were highly influenced by stratification. We estimated the rate of kinetic energy dissipation, , from YODA Profiler data based on the Thorpe scale approach. We also estimated the eddy diffusivity coefficient, . Both and followed a lognormal probability density function. The mean was consistent with a one‐dimensional diffusion model assessed from the R2 values of flow speed and backscatter intensity. 相似文献
52.
The establishment of no‐take marine reserves has been increasingly promoted as a key measure to achieve conservation and sustainability goals in fisheries. Regardless of the wide range of benefits cited, the effectiveness of reserve establishment depends critically on fisheries management outside the reserves. We construct a bioeconomic model of a fishery that allows for the establishment of a no‐take marine reserve and evaluate how the choice of the off‐reserve management target influences the effectiveness of reserve establishment. We evaluate two biomass targets: (i) BMSY or the biomass that produces the maximum sustainable yield (MSY) and (ii) BMEY or the biomass that maximizes the net present value of the returns to fishing. The parameterized model shows that, for a wide range of scenarios, the fishery will be better off in terms of both conservation and economic objectives when the no‐take reserve is established in conjunction with the BMEY target rather than with the BMSY target. Model results further show that the opportunity cost of securing additional fish biomass, in both deterministic and stochastic environments, is lower when the reserve size is increased under the BMEY target. This finding is important because marine reserves have been established as a key measure to restore depleted fish stocks, and the results suggest that this objective can be achieved with lower economic costs in a BMEY managed fishery. 相似文献
53.
Yamazaki H Wewengkang DS Nishikawa T Rotinsulu H Mangindaan RE Namikoshi M 《Marine drugs》2012,10(2):349-357
Two new tryptamine-derived alkaloids, named as leptoclinidamide (1) and (-)-leptoclinidamine B (2), were isolated from an Indonesian ascidian Leptoclinides dubius together with C2-α-D-mannosylpyranosyl-L-tryptophan (3). The structure of 1 was assigned on the basis of spectroscopic data for 1 and its N-acetyl derivative (4). Compound 1 was an amide of tryptamine with two β-alanine units. Although the planar structure of 2 is identical to that of the known compound (+)-leptoclinidamine B (5), compound 2 was determined to be the enantiomer of 5 based on amino acid analysis using HPLC methods. Compounds 1 to 4 were evaluated for cytotoxicity against two human cancer cell lines, HCT-15 (colon) and Jurkat (T-cell lymphoma) cells, but none of the compounds showed activity. 相似文献
54.
<Emphasis Type="Italic">Turnip yellow mosaic virus</Emphasis> isolated from Chinese cabbage in Japan
Namiko Kirino Koji Inoue Koji Tanina Yuya Yamazaki Satoshi T. Ohki 《Journal of General Plant Pathology》2008,74(4):331-334
A virus that caused a distinct yellow mosaic was isolated in Okayama, Japan from Chinese cabbage (Brassica rapa L., Pekinensis group). The virus, with spherical particles ca. 28 nm in diameter, was mechanically transmissible only to
cruciferous species. From the host range, characteristic morphology of virus particles, serology and sequence analysis of
coat protein gene, the causal virus was identified as Turnip yellow mosaic virus (TYMV). Seed transmission of TYMV at 0–2.2% in Chinese cabbage was confirmed. This report is the first of TYMV from Chinese
cabbage and in Japan.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases as accessions AB358971 and AB358972. 相似文献
55.
Naoya Yamaguchi Takashi Sayama Hiroyuki Yamazaki Tomoaki Miyoshi Masao Ishimoto Hideyuki Funatsuki 《Breeding Science》2014,64(4):300-308
Lodging tolerance (LT) is an important trait for high yield and combine-harvesting efficiency in soybean [Glycine max (L.) Merr.]. Many previous studies have investigated quantitative trait loci (QTLs) for lodging score (LS) in soybean. Most of the investigated QTLs were located in the proximal region of maturity or growth habit loci. The aim of this study was to identify genetic factors for LT not associated with maturity or growth habit. QTL analysis was performed using a recombinant inbred line (RIL) population derived from a cross between ‘Toyoharuka’ (TH), a lodging-tolerant cultivar, and ‘Toyomusume’ (TM). The genotypes of TH and TM were estimated as both e1e2E3E4 and dt1. The average LS over 4 years was used for QTL analysis, identifying a major and stable QTL, qLS19-1, on chromosome 19. The LS of the near-isogenic line (NIL) with the TH allele at Sat_099, the nearest marker to qLS19-1, was significantly lower than the NIL with the TM allele at that position. The TH allele at Sat_099 rarely had a negative influence on seed yield or other agronomic traits in both NILs and the TM-backcrossed lines. Our results suggest that marker-assisted selection for qLS19-1 is effective for improving LT in breeding programs. 相似文献
56.
57.
Tropical Animal Health and Production - We evaluated the relationship between the temperature–humidity index (THI) and health and growth performance in Japanese black calves in Japan. Data... 相似文献
58.
Kazuhiro HARA Hideki WATABE Shinji SASAZAKI Fumio MUKAI Hideyuki MANNEN 《Animal Science Journal》2010,81(2):152-157
This study describes the development of efficient single nucleotide polymorphism (SNP) markers for individual identification and parentage tests in a Japanese Black cattle population. An amplified fragment length polymorphism method was employed to detect informative candidate markers, and yielded 44 SNP markers from 220 primer combinations. 29 unlinked SNPs were finally selected as diagnostic markers. The allelic frequencies for each marker were estimated by using PCR‐RFLP in the Japanese Black population. Based on the frequency data, the estimated identity power of these markers was 2.73 × 10?12. Parentage exclusion probabilities, when both suspected parents' genotypes were known and when only one suspected parent was genotyped, were estimated as 0.96929 and 0.99693, respectively. This panel of SNP markers is theoretically sufficient for individual identification, and would also be a powerful tool for a parentage test in Japanese Black cattle. The markers could contribute to the management of the beef industry in Japan. 相似文献
59.
Uno Y Matsuno K Nakamura C Utoh M Yamazaki H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):487-490
Cytochrome P450 (CYP) is important for metabolism of not only xenobiotics such as drugs, but also endogenous compounds including arachidonic acids. CYP4A11, CYP4F3v2, CYP4F11, and CYP4F45 have been identified in cynomolgus macaque, an animal species widely used for investigation of drug metabolism due to its evolutionary closeness to human. However, their metabolic functions have not been investigated. In this study, proteins were heterologously expressed in Escherichia coli and characterized by metabolic assays using arachidonic acids as substrates that are metabolized by CYP4 isoforms in human. The results showed that all four CYPs metabolized arachidonic acids. Therefore, cynomolgus macaque CYP4A11, CYP4F3v2, CYP4F11, and CYP4F45 are functional enzymes. 相似文献
60.
Doi Y Tamano S Kawabe M Sano M Imai N Nakashima H Furukawa F Hagiwara A Otsuka M Shirai T 《Journal of toxicologic pathology》2011,24(4):207-213
This study was conducted to determine the concordance of results for a pair of structural
isomers, 2-nitropropane (2-NP) and 1-nitropropane (1-NP), using the rat medium-term liver
carcinogenesis bioassay (Ito test) and previously published long-term carcinogenicity
tests. Male F344 rats were given a single intraperitoneal injection of DEN (200 mg/kg
b.w.) to initiate hepatocarcinogenesis. After 2 weeks, they received per os 0, 0.8, 4 or
20 mg/kg/day of 2-NP or 1-NP six times a week and were subjected to two-thirds partial
hepatectomy at week 3. Non-initiated groups receiving 0 or 20 mg/kg/day were also
included. The animals were sacrificed for quantitative analysis of GST-P-positive foci at
week 8. With the highest dose of 2-NP, significantly increased numbers and areas of
GST-P-positive foci were demonstrated as compared with the respective control but were not
noted with 1-NP. In the non-DEN-initiated groups, many small GST-P-positive foci of less
than 0.2 mm in diameter were also induced in the rats treated with 2-NP at 20 mg/kg/day
but were lacking with 1-NP. These results strongly support that 2-NP is a complete
hepatocarcinogen with a potent initiation activity, whereas 1-NP is not. 相似文献