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101.
102.
Kei Ishida Macarius Yangyuoru Koichi Unami Toshihiko Kawachi 《Paddy and Water Environment》2011,9(4):393-401
Analysis of runoff processes in farmlands during storm events in particular is an important engineering topic. The shallow
water equations describing the physical conservation laws are attractive tools for understanding motion of surface water.
A numerical model is developed to reproduce surface water flows during storm events, using the finite element method and the
finite volume method applied to the one-dimensional shallow water equations. The numerical model has the advantage of dealing
with transcritical flows, wet, and dry processes, irregular channel bed slopes, and channel junctions involving multiply connected
networks. Standard numerical tests demonstrated some of these features. Runoff processes from farmlands in a Japanese hilly
area is analyzed with the numerical model coupled with another runoff model of black-box type. Parameters of the models are
calibrated and validated using observed series of rainfall and runoff discharge data. Simulated results included submergence
of hydraulic jumps and flood storage in farming plots, which are very informative in terms of assessing diverse functions
of the farmlands. 相似文献
103.
Shunsuke Chono Shigeya Maeda Toshihiko Kawachi Chie Imagawa Natsuki Buma Junichiro Takeuchi 《Paddy and Water Environment》2012,10(2):113-120
An optimization model for cropping-plan placement on field plots is presented for supporting decision-making on agricultural management by a farming organization. The mixed 0?C1 programming technique is employed to select the next planting crop at each field plot in a holistic manner. Reduction of total nitrogen discharged from field plots to the downstream end of the drainage canals is expressed as an objective function of the model to balance an achievement of economic goal and environmental conservation. Some Japanese governmental policies on regulating rice cropping areas and on promoting production of particular upland field crops can be formulated in the model. A computational example of cropping-plan placement on field plots managed under integrated policies is given by operating the optimization model with various weights associated with the objectives. The procured trade-off curve and corresponding patterns of cropping-plan could be useful in the decision-making by the farming organization. 相似文献
104.
105.
Anzai Toshihiko Ikeura Hiroshi Chomxaythong Amphone Keokhamphui Khaykeo Inkhamseng Somphone 《Paddy and Water Environment》2019,17(4):633-650
Paddy and Water Environment - The rural area in Lao PDR has a low yield of rainy season lowland rice, and most rice fields are not utilized for crop cultivation during the dry season. Delay in... 相似文献
106.
Tsutsui T Tezuka T Mikasa Y Sugisawa H Kirihara N Hori T Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):307-312
Cooled canine semen solutions for storage were investigated with three stock solutions: egg yolk-citrate-glycine-glucose solution, egg yolk Tris-fructose citrate solution (EYT-FC), and egg yolk sodium citrate dihydrate solution (EYCD). For the control group, the second fraction of semen was examined. Nine male beagles and 37 female (47 experimental cases) beagles for artificial insemination (AI) were used. The qualities of semen stored at 4 degrees C deteriorated earlier in the control and EYCD groups. In the other two groups, sperm motility was 60% or higher after storage for 6 days and 20% or higher after storage for 12 days. On a comparison of these two groups, the sperm motility and viability were slightly higher in the EYT-FC group. A high conception rate was obtained by AI using semen stored at a low temperature for a maximum of two days in the control group and four days in the EYT-FC group. 相似文献
107.
Kawakami E Koga H Hori T Tsutsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):409-412
A mongrel dog, aged 2 years, was found to have only a small number of sperm, immobilization of all sperm, and many sperm agglutinations in its ejaculates, and scrotal palpation revealed a small nodule in the left cauda epididymis. Addition of the dog's seminal plasma or serum to the semen of 2 normal dogs caused immobilization and agglutination of their sperm. Histological examination showed that the nodule was a sperm granuloma. Many lymphocytes were seen in the stroma around the sperm granuloma. Anti-sperm antibodies are presumed to be present in the semen and serum of the asthenozoospermic dog. 相似文献
108.
Hori T Akikawa T Kawakami E Tsutsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(9):807-811
The effects of the long-acting prostagrandin F(2)(alpha)-analogue fenprostalene were investigated. Twenty-three female beagles (24 cases) 1-6 years of age were divided into 6 groups, and a dose of 5-150 microg/head of fenprostalene was subcutaneously administered at 25 days after ovulation to investigate its effects based on peripheral blood progesterone (P(4)) levels. The dogs were also examined for shortening of their estrous cycle after administration and fecundity after the recurrence of estrus. The results showed that the administration of 50 microg/head of fenprostalene or more reduced the levels of peripheral blood P(4) to about 1 ng/ml 2 days after administration, indicating early regression of the corpus luteum, and that the administration of these doses shortened the time to the subsequent estrus by a mean of about 80 days, and that conception rates were normal if estrus recurred about 2 months after fenprostalene administration or later. 相似文献
109.
Zulu VC Nakao T Sawamukai Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(8):657-665
The current review aims to establish insulin-like growth factor-1 (IGF-I) as the factor that signals nutritional status to the reproductive axis, and show that assessment of IGF-I in blood early postpartum during the negative energy balance (NEB) period could be used to predict both nutritional and reproductive status in dairy cattle. The review also explores the effect of nutritional status on circulating IGF-I concentrations and the endocrine role of IGF-I on the reproductive axis. IGF-I plays an important role in gonadotropin-induced folliculogenesis, ovarian steroidogenesis and corpus luteum (CL) function. It also modulates pituitary and hypothalamus function. IGF-I clearly has an endocrine role on the reproductive axis. Severe under nutrition significantly reduces plasma IGF-I concentrations. During the critical period of NEB in high yielding dairy cattle early postpartum, IGF-I concentrations are low in blood and its levels are positively correlated to energy status and reproductive function during this period. Changes in circulating IGF-I immediately postpartum may help predict both nutritional and reproductive status in dairy cattle. IGF-I is therefore one of the long sought factors that signal nutritional status to the reproductive axis. 相似文献
110.
Kapil D. SHAH Toshihiko NAKAO Hirokazu KUBOTA Teruo MAEDA 《Animal Science Journal》2007,78(5):489-494
The aim was to evaluate the relationship of prepartum plasma estrone sulfate (E1S) and estradiol‐17β (E2β) concentrations with the weight of the calf and the placental parameters. Holstein–Friesian cows (n = 33) inseminated artificially with Japanese Black beef bull semen at Hiroshima University Farm in Japan were used for the experiment. Blood samples were taken every day from day 270 of gestation until the day after calving. The plasma samples were analyzed for E1S and E2β by enzyme immunoassay. The calf birth weight was taken immediately after calving. Complete fetal membranes were collected from 19 cattle and the weights of the placental components and the number of cotyledons were recorded. All 33 cattle delivered singleton normal calves. The prepartum plasma E1S concentration was found to correlate significantly (P < 0.01) with the calf birth weight (r = 0.83), total fetal membrane weight (r = 0.81), cotyledonary weight (r = 0.79) and inter‐cotyledonary membrane weight (r = 0.64), but it did not correlate significantly with the number of cotyledons, whereas prepartum plasma E2β was not found to correlate significantly with the weight of either the calf or any of the placental components except the number of cotyledons. In conclusion, prepartum plasma E1S, not plasma E2β, was found to correlate significantly with the weight of the calf and the placental components. 相似文献