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排序方式: 共有763条查询结果,搜索用时 15 毫秒
631.
Saito Rui Sasaki Hiroaki Yamada Haruya Hiroe Yutaka Inagake Denzo Saito Tsutomu 《Fisheries Science》2020,86(1):13-25
Fisheries Science - The East China Sea is a semi-enclosed sea, surrounded by Japan, China, South Korea and Taiwan, and is continuously influenced by lit fishing vessels overexploiting fishery... 相似文献
632.
Toshihiko Saito Ikutaro Shimizu Jiro Seki Toshiki Kaga Eiichi Hasegawa Hiromi Saito Kazuya Nagasawa 《Fisheries Science》2010,76(6):909-920
To examine the efficacy of juvenile salmon research as a tool for forecasting adult returns, the results from a study on the
early marine life stage of juvenile chum salmon, conducted in the Nemuro Strait during 1999–2002 (i.e., 1998–2001 brood years),
were compared with the return rates of adult salmon. Among the four brood years, the 2000 brood year (i.e., salmon migrating
to the sea in 2001) was previously reported as showing higher abundance, higher growth rate and better somatic condition during
the coastal residency period. Consequently, we expected it to have the highest return rate, under a hypothesis that juvenile
survival in coastal residency regulates brood-year strength. Contrary to this expectation, the 2000 brood year had almost
the lowest return rate. Alternatively, a statistical model in which sea surface temperature during the first year of marine
life and size at release were utilized as explanatory variables reconstructed the actual variability in return rates more
accurately than that based on the early marine life stage. Possible reasons for the discrepancy between the results of the
juvenile salmon research and adult returns are discussed, and we suggest improvements for future research on juvenile salmon. 相似文献
633.
Kojima Hajime Kohgo Yuji Shimada Kiyoshi Shoda Daisuke Suzuki Hisato Saito Hirotaka 《Paddy and Water Environment》2020,18(2):431-442
Paddy and Water Environment - The 2011 Tohoku earthquake damaged many small earthen dams in Japan, causing flood damage and human casualties. Since then, the necessity for developing accurate... 相似文献
634.
Marc Cotter Folkard Asch Bayuh Belay Abera Boshuwenda Andre Chuma Kalimuthu Senthilkumar Arisoa Rajaona Ando Razafindrazaka Kazuki Saito Sabine Stuerz 《Journal of Agronomy and Crop Science》2020,206(4):423-432
Increasing demand for land to ensure human food security in the future has already impelled agricultural production into marginal areas. The environmental conditions found there have a more pronounced impact on agricultural productivity than in the systems used so far under favourable conditions. In addition to this challenge, climate change is expected to increase the unreliability of weather conditions (through increased variability and occurrence of extremes) for farmers considerably. This unreliability is even more serious in developing countries’ farming system where food security is vulnerable. Current efforts in digitalization offer great possibilities to improve farmers` decision-making processes. A wide range of online tools and smartphone applications is available to support both agricultural extension services and smallholder farmers alike. These apps are often parameterized and validated to certain environments and are troubled when applied to new geographical locations and different environmental conditions. We have conducted field trials to demonstrate potential methods to close knowledge gaps in the data background for one of these apps, RiceAdvice, concerning three key aspects: shifting of cropping calendar, adjustment of fertilizer management and genotype selection. Sites in Ethiopia, Madagascar and Rwanda were selected to represent altitudinal gradients, with overlapping elevations reflecting differences in temperature to enable cross-country comparisons. Planting dates were distributed throughout three calendar years, with continuous iterative planting dates taking place in Madagascar, in- and off-season planting dates in Rwanda with different fertilizer applications, and one planting date during each rainy season in Ethiopia with different management options. With these trials, we have been able to identify key data sets needed for the adaptation of agricultural decision support tools to new environments. These include the assessment of climatic constraints on innovations to cropping calendars (e.g. double cropping), informed selection of alternative varieties able to complete crucial parts of their phenological development to avoid temperature-related stress inducing, for example spikelet sterility in rice in late development stages and the effectivity of potential innovations in fertilizer management strategies. 相似文献
635.
Muhammad I Illijas Masaru Terasaki Ryo Nakamura Noriaki Iijima Akihiko Hara Nobuhiro Fusetani Yutaka Itabashi 《Fisheries Science》2008,74(3):670-676
ABSTRACT: A glycerolipid acyl-hydrolase was purified 19-fold with a yield of 11% from the prostaglandin-producing red alga Gracilaria vermiculophylla by ammonium sulfate precipitation, anion-exchange chromatoraphy and gel filtration chromatography. Sodium dodecylsulfate– polyacrylamide gel electrophoresis of the final preparation showed a single band corresponding to a molecular mass of 20 kDa, but Superdex 200 fast protein liquid chromatography exhibited a molecular mass of 40 kDa. Accordingly, it was suggested that the purified enzyme was a homodimer of a 20 kDa subunit. The optimal temperature and pH were 37°C and 7–8, respectively. The purified enzyme catalyzed hydrolysis of the acyl groups of both glycoglycerolipids and phospholipids, especially monogalactosyldiacylglycerol and phosphatidylcholine. These results suggest that the enzyme hydrolyze the membrane lipids of the alga to release various saturated and unsaturated fatty acids, including arachidonic acid as substrate for prostaglandin synthesis. 相似文献
636.
Kazuhito Ichii Masayuki Kondo Young-Hee Lee Shao-Qiang Wang Joon Kim Masahito Ueyama Hee-Jeong Lim Hao Shi Takashi Suzuki Akihiko Ito Hyojung Kwon Weimin Ju Mei Huang Takahiro Sasai Jun Asanuma Shijie Han Takashi Hirano Ryuichi Hirata Tomomichi Kato Sheng-Gong Li Ying-Nian Li Takahisa Maeda Akira Miyata Yojiro Matsuura Shohei Murayama Yuichiro Nakai Takeshi Ohta Taku M. Saitoh Nobuko Saigusa Kentaro Takagi Yan-Hong Tang Hui-Min Wang Gui-Rui Yu Yi-Ping Zhang Feng-Hua Zhao 《Journal of Forest Research》2013,18(1):13-20
Based on the model–data comparison at the eddy-covariance observation sites from CarboEastAsia datasets, we report the current status of the terrestrial carbon cycle modeling in monsoon Asia. In order to assess the modeling performance and discuss future requirements for both modeling and observation efforts in Asia, we ran eight terrestrial biosphere models at 24 sites from 1901 to 2010. By analyzing the modeled carbon fluxes against the CarboEastAsia datasets, the strengths and weaknesses of terrestrial biosphere modeling over Asia were evaluated. In terms of pattern and magnitude, the carbon fluxes (i.e., gross primary productivity, ecosystem respiration, and net ecosystem exchange) at the temperate and boreal forest sites were simulated best, whereas the simulation results from the tropical forest, cropland, and disturbed sites were poor. The multi-model ensemble mean values showed lower root mean square errors and higher correlations, suggesting that composition of multiple terrestrial biosphere models would be preferable for terrestrial carbon budget assessments in Asia. These results indicate that the current model-based estimation of terrestrial carbon budget has large uncertainties, and future research should further refine the models to permit re-evaluation of the terrestrial carbon budget. 相似文献
637.
Masahito Nanamori Yoshiro Tokizono Takehiro Hoki Wataru Saito Ryota Aritomo Tsutomu Yamaki Naohiko Hirota Narushi Suda Aaron Beattie 《Breeding Science》2021,71(2):277
Various types of malt quality profiles have been investigated to benefit the North American brewing industry. Herein, we report the development and brewing quality of the hulled, two-row malting barley (Hordeum vulgare L.) variety ‘CDC Goldstar’ lacking lipoxygenase-1 (LOX-1-less). This new variety offers a novel malt type for the improvement of beer flavor stability. The agronomic performance of ‘CDC Goldstar’ was tested in the Western Cooperative Two Row Barley Registration Trials during 2013–2014. In addition to high lodging tolerance, the new variety showed 6% higher yield than the current leading variety ‘CDC Copeland’. The malt quality of ‘CDC Goldstar’ showed higher diastatic power and lower wort β-glucan content than ‘CDC Copeland’ and controllable proteolytic modification (soluble nitrogen and Kolbach Index). Pilot- (100 L) and commercial-scale (5,000 L) brewing trials were conducted using ‘CDC PlatinumStar’, another LOX-1-less variety with a low enzymatic profile, as the control variety. Absence of the LOX-1 trait from ‘CDC Goldstar’ maintained trans-2-nonenal levels in aged beers as low as those in other LOX-1-less varieties without affecting major beer parameters, such as ester and aldehyde content or foam stability. The newly developed ‘CDC Goldstar’ malting barley provides added value for the beer industry and consumers. 相似文献
638.
Free radical scavenging activity and antiulcer activity of garcinol from Garcinia indica fruit rind 总被引:2,自引:0,他引:2
Yamaguchi F Saito M Ariga T Yoshimura Y Nakazawa H 《Journal of agricultural and food chemistry》2000,48(6):2320-2325
Garcinol, a polyisoprenylated benzophenone derivative, was purified from Garcinia indica fruit rind, and its free radical scavenging activity was studied using electron spin resonance (ESR) spectrometry. In the hypoxanthine/xanthine oxidase system, emulsified garcinol suppressed superoxide anion to almost the same extent as DL-alpha-tocopherol by weight. In the Fenton reaction system, garcinol also suppressed hydroxyl radical more strongly than DL-alpha-tocopherol. In the H(2)O(2)/NaOH/DMSO system, garcinol suppressed superoxide anion, hydroxyl radical, and methyl radical. It was thus confirmed that this derivative is a potent free radical scavenger and able to scavenge both hydrophilic and hydrophobic ones including reactive oxygen species. Orally administered garcinol prevented acute ulceration in rats induced by indomethacin and water immersion stress caused by radical formation. These results suggested garcinol might have potential as a free radical scavenger and clinical application as an antiulcer drug. 相似文献
639.
Muñana KR Saito M Hoshi F 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(2):173-178
BACKGROUND: Cerebrospinal fluid (CSF) analysis is the basis for establishing a diagnosis of central nervous system (CNS) inflammation. However, the information provided by routine CSF analysis is limited. Determination of CSF beta-2-microglobulin (beta2m) concentration has been used diagnostically in humans to identify inflammatory CNS disease; we hypothesized that it may have similar value in dogs. OBJECTIVES: The objective of this study was to measure (beta2m concentration in the CSF of clinically healthy dogs and compare the values to those observed in dogs with inflammatory CNS disease and intervertebral disc disease (IVDD). METHODS: CSF was collected from 10 clinically healthy laboratory dogs and 11 dogs each with inflammatory CNS disease and IVDD. Routine CSF analysis was performed, and (beta2m concentration was measured by ELISA. CSF (beta2m concentration and CSF:serum (beta2m ratio were compared between groups by ANOVA. Linear relationships between CSF total nucleated cell count (TNCC), RBC count, total protein concentration, and (beta2m concentration were assessed by regression analysis. RESULTS: The mean (+/- SD) CSF (beta2m concentration in clinically healthy dogs was 0.36 (+/- 0.05 microg/mL (cisternal) and 0.40 (+/- 0.07 microg/mL (lumbar). Median CSF (beta2m concentration in dogs with IVDD (0.46 microg/mL) and inflammatory CNS disease (0.85 microg/mL) differed from that of controls (0.36 microg/mL; P=.002). The concentration also differed between the 2 disease groups (P=.01). Five dogs with inflammatory CNS disease had CSF:serum (beta2m ratios >1. A correlation was identified between TNCC and (beta2m concentration (r=0.69, P=.0003). CONCLUSIONS: CSF (beta2m concentration is higher in dogs with IVDD and inflammatory CNS disease, with highest values seen with inflammatory disease. This may be attributed in part to the correlation between CSF (beta2m concentration and TNCC, but also may reflect intrathecal immune activation. 相似文献
640.
Akihiko SUGIYAMA Jing SUN Kota UEDA Satoshi FURUKAWA Takashi TAKEUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):789-797
Six-day-old rats were treated intraperitoneal injections with methotrexate 1
mg/kg, and the cerebellum was examined. Both the length and width of the vermis decreased
in the methotrexate-treated group instead of the control from 4 day after treatment (DAT)
onward. A significant reduction in the width of the external granular layer was detected
on 2 and 3 DAT in the methotrexate group. By 4 DAT, the width of the external granular
layer of the methotrexate group was indistinguishable from the control, and by 8 DAT, it
was greater than that of the control. The molecular layer of methotrexate group on 8 and
15 DAT was thinner than that of the control. On 1 DAT, in the methotrexate group, there
were many TUNEL and cleaved caspase-3-positive granular cells throughout the external
granular layer, and they decreased time-dependently. On 1 DAT, in the methotrexate group,
phospho-histone H3-positive cells in the external granular layer were fewer than in the
control and tended to increase on 2–4 DAT. The p21-positive-rate of the external granule
cells in the MTX group was higher than in the control on 1–4 DAT. These results suggested
that methotrexate exposure on postnatal day 6 induces a delay, slowing in the migration of
external granular cells to the inner granular layer, attributed to decrease or inhibition
in the production of external granular cells that had arisen from apoptosis and the
decrease in cell proliferative activity, resulting in cerebellar hypoplasia. 相似文献