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排序方式: 共有626条查询结果,搜索用时 15 毫秒
571.
Satoshi Kono Tassanee Ounvichit Atsushi Ishii Masayoshi Satoh 《Paddy and Water Environment》2012,10(1):75-81
In principle, participatory irrigation management (PIM) means the involvement of irrigation users in all aspects at all levels
of irrigation management. In practice, all over the world efforts are being made to realize the principles. However, in the
execution of PIM, role sharing between farmers and government is a serious problem, and thus a clear method and ideas are
needed to improve PIM. In particular, a broad discussion of role sharing is demanded. This article illustrates how the Japanese
way of role sharing in PIM is realized based on the case of the Toyogawa Irrigation Project. Organizationally, the project
is jointly managed by five entities, including both the public sector and the farmers’ organizations. These entities have
clearly divided their functional roles, with the ultimate decision power in all aspects of irrigation management given to
organized farmers. The power is realized either directly or through the land improvement districts’ representative system
depending on the levels of the irrigation system. The public entity provides coordination support to create a transparent
forum of discussion together with scientific information for farmers’ understanding and decision making. The participatory
institutional line-up of this project enables the upland areas that suffered periodically from water deficits. 相似文献
572.
573.
Akira?KawakamiEmail author Naoki?Kato Takahide?Sasaya Keisuke?Tomioka Hiroyoshi?Inoue Atsushi?Miyasaka Kazuyuki?Hirayae 《Journal of General Plant Pathology》2015,81(4):324-327
Ear rot with white or pink mold was found on corn (Zea mays L.). A species of Fusarium, not registered previously as a pathogen causing Gibberella ear rot of corn in Japan, was isolated from the rotted ear. The isolates, identified as F. asiaticum based on morphological characteristics and nucleotide sequences, caused white or pink mold on corn ear after inoculation. Moreover, the 3-acetyl deoxynivalenol chemotype and the nivalenol chemotype were found in the isolates. We propose to include F. asiaticum as one of the pathogens causing Gibberella ear rot of corn in Japan. 相似文献
574.
Masanori Takahashi Michio Yoneda Hajime Kitano Atsushi Kawabata Mami Saito 《Fisheries Science》2014,80(2):293-300
The growth of juvenile chub mackerel Scomber japonicus collected in the western North Pacific Ocean in 2007 and 2009 was examined based on the evidence of otolith daily increment formation in captive specimens. There was a significant difference in the relationship between known age and number of increments in the frontal and sagittal planes. Repeated markings on the otolith using Alizarin complexone and the coefficient of variation in number of increments suggest that the increments in the frontal plane of the otolith are more suitable for age estimation than those in the long and short axes of the sagittal plane. The increments in the frontal plane formed daily, and the first ring was usually deposited 3 days after hatch. Age of wild juveniles ranged from 24 to 211 days after hatch based on the frontal plane method. The estimated hatching periods of specimens ranged from February to June, but the April-hatched specimens were collected throughout the sampling periods of 2007 and 2009. The Gompertz growth model showed a difference in growth pattern in specimens between 2007 and 2009. The juveniles in 2009 appeared to grow more quickly than those in 2007 until summer, but thereafter the 2009 specimens seemed to grow more slowly. 相似文献
575.
Shiga A Ota Y Ueda Y Hosoi M Miyajima R Hasegawa K Mizuhashi F 《Journal of toxicologic pathology》2010,23(4):253-260
Focal granulomatous inflammation developed in the livers of five 10-week-old male Sprague-Dawley rats. The characteristic features of this lesion were the presence of foreign body multinucleated giant cells engulfing calcium deposits and site-specific development in a fissure formed in a sub-lobation in the left lobe or interlobar fissure of the medial lobe of the liver. To clarify the pathogenesis of this lesion, rat livers showing abnormal sub-lobation or lobar atrophy, rat livers in an acute dermal toxicity study and guinea pig livers in a skin sensitization test were also examined histologically. Consequently, the present lesion was considered to be a reactive change against calcium that was dystrophically deposited in the area of hepatocellular necrosis due to delayed circulatory disturbance caused by external pressure or extension force. Granulomatous lesions like in the present cases should be differentiated from those caused by evident exogenous pathogens such as chemicals or microorganisms. 相似文献
576.
Promotion of initial swim bladder inflation and effect of initial inflation failure on skeletal malformation in cultured seven‐band grouper Hyporthodus septemfasciatus (Thunberg)
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Masaharu Tsuji Susumu Uji Yasushi Tsuchihashi Kazuhiro Okada Takeshi Kawamura Takashi Katoh Tohru Kasuya Takuo Nigo Atsushi Hamabe Atsushi Miyamoto Sahoko Nakamura Akiko Nakano Yoshifumi Sawada 《Aquaculture Research》2016,47(6):1954-1971
The effects of the removal of the oily surface film on initial swim bladder inflation and survival in cultured seven‐band grouper Hyporthodus septemfasciatus were investigated during the larval stage. Additionally, the relationship between swim bladder inflation failure and malformations in later stages was examined. To explore promotion conditions for inflation, duplicate experiments were conducted under three different water surface conditions: removal of the oily surface film (ROF group), covering the water surface with an oil film (COF group), and sealing the water surface with liquid paraffin (SLP group). Larval swim bladder inflation was first observed 14 days after hatching (DAH) in the ROF group; thereafter, swim bladder inflation rates increased to 11.1% and 38.7% until the end of the experiments. This indicates that initial swim bladder inflation occurs at the pre‐flexion stage in larval development. Conversely, bladder inflation was rarely observed in the COF or SLP groups, indicating the promotional effect of surface film removal on larval swim bladder inflation and suggesting that gulping atmospheric air is necessary for initial inflation. Although larval water surface death occurred frequently in the ROF group, no significant difference existed in any group between the survival rates at 10 DAH and at the end of the experiment. The incidence rate of spinal curvature and deformation of the centra was significantly higher in individuals without initial swim bladder inflation, and these malformations mainly occurred in the caudal vertebra. Therefore, the removal of the oily surface film promotes initial swim bladder inflation and reduces larval malformations. 相似文献
577.
578.
Kiyohiko Fujimoto Yasushi Hiramatsu Atsushi Miyatake Kenta Shindo Masahiko Karube Masaki Harada Seiichiro Ukyo 《Journal of Wood Science》2010,56(6):444-451
The object of this study was to investigate the strength properties of edge-glued laminae and to propose a suitable grading
method based on the lamina modulus of elasticity (MOE). Edge-glued laminae composed of lumber with similar MOEs (uniform laminae)
and edge-glued laminae produced by randomly gluing lumber independent of MOE (random laminae) were made from karamatsu (Larix kaempferi) lumber having the same thickness and length, but various widths. For both the uniform and random laminae, there was a strong
correlation between MOE values measured using the longitudinal vibration technique, the static bending test, and a grading
machine. The average values of bending, tensile, and compressive strengths of the uniform laminae were similar to those of
the random laminae. On the other hand, the average strength of laminae without end joints was significantly higher than that
of finger-jointed laminae for both uniform and random laminae. Finger-joints and knots played a significant role in the failure
of specimens, but the edge-gluing and the difference in MOE within an edge-glued lamina did not appear to affect the strength
properties. The bending, tensile, and compressive strengths of edge-glued laminae were strongly correlated to the lamina MOE. 相似文献
579.
The antihyperglycemic effects of the leaves of Acer amoenum and purification and identification of an active compound were investigated. In screening experiments for α-glucosidase inhibitory activity, methanolic extracts of A. amoenum leaves showed potent inhibitory action. This extract showed antihyperglycemic effects in sucrose-loaded mice. Fractionation
of the crude extract gave the active compound corilagin [β-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-d-glucose] by spectroscopic analysis. This is the first report about the possibility of novel utilization of the Japanese maple
tree as a source of compounds for prevention or treatment of diabetes mellitus. 相似文献
580.
A spectrophotometric assay based on the color reaction between didecyldimethylammonium chloride (DDAC) and 4-[4-(dipropylamino)phenylazo]-benzenesulfonic acid (propyl orange) was used for the determination of DDAC as a wood preservative. The assay was carried out using a propyl orange solution at pH 2.9. The visible absorbance spectrum of propyl orange showed an absorbance maximum at 510 nm, which decreased continuously with increasing DDAC concentration from 0 to 20 ppm. A linear correlation was observed at a DDAC concentration lower than 8 ppm. To apply this assay method to determine DDAC retention in treated wood, the influence of wood extractives on the assay was investigated. Wood extractives from sapwood and heartwood of Japanese cedar, Hinoki cypress, Japanese larch, and Western hemlock showed no influence on DDAC determination except in the case of heartwood from Japanese cedar and Hinoki cypress, which gave apparent DDAC concentrations higher than the actual values. However, it was also found that absorbance measurement at 477 nm solved this overestimation and gave precise values. It was concluded that this assay is a viable alternative to the current methods for DDAC determination. 相似文献