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81.
Shoji T Masumoto S Moriichi N Akiyama H Kanda T Ohtake Y Goda Y 《Journal of agricultural and food chemistry》2006,54(3):884-892
In this study, we investigated the absorption of apple procyanidins, namely, apple condensed tannins (ACTs), in rats using the Porter method and high-performance liquid chromatography/tandem mass spectrometry. The apple procyanidin concentrations in the rat plasma reached a maximum 2 h after administration and decreased thereafter. To investigate the limits of the absorption of apple procyanidins in the polymerization degree, we administered the procyanidin oligomer fraction, which was separated from ACT using normal-phase chromatography according to the degree of polymerization. Procyanidins from each dimer to pentamer group were detected in the plasma by the Porter method. Moreover, by the study using reconstituted procyanidins, polymeric procyanidins influenced the absorption of procyanidin oligomers. These results suggest that ACTs are absorbed and directly involved in physiological functions in the rats. 相似文献
82.
83.
Influence of riders’ skill on plasma cortisol levels of horses walking on forest and field trekking courses 下载免费PDF全文
Ayaka Ono Akihiro Matsuura Yumi Yamazaki Wakako Sakai Kentaro Watanabe Toshihiko Nakanowatari Hiroshi Kobayashi Mami Irimajiri Koichi Hodate 《Animal Science Journal》2017,88(10):1629-1635
The aim of this study was to evaluate the influence of rider's skill on the plasma cortisol levels of trekking horses on two courses, walking on field and forest courses (about 4.5 to 5.1 km each). Three riders of different skills did horse trekking (HT) in a tandem line under a fixed order: advanced‐leading, beginner‐second and intermediate‐last. A total of six horses were used and they experienced all positions in both courses; a total of 12 experiments were done. Blood samples were obtained before HT, immediately after and 2 h after HT. As a control, additional blood samples were obtained from the same horses on non‐riding days. Irrespective of the course and the rider's skill, the cortisol level before HT was higher than that of control (P < 0.05). In both courses, the cortisol levels immediately after HT ridden by the advanced rider were higher than that of control (P < 0.05). However, in every case, the cortisol level 2 h after HT was closely similar to the level of the control. Thus, we concluded the stress of trekking horse was not sufficient to disturb the circadian rhythm of the cortisol level, irrespective of the course and the rider's skill. 相似文献
84.
Koichi Unami Kei Ishida Toshihiko Kawachi Shigeya Maeda Junichiro Takeuchi 《Paddy and Water Environment》2010,8(2):105-111
Adults of Carassius auratus grandoculis ascend from Lake Biwa, Japan, into riparian paddy fields via agricultural drainage systems for the purpose of spawning. However,
land improvement works conducted in the second half of the twentieth century have brought about obstacles for passage of the
fish, and several restoration projects to recover the migratory environment are being attempted. A continuous Markov process
model is presented to scientifically support such a project, defining an ascending probability that quantitatively assesses
the ability of an agricultural drainage system with hydraulic structures for the ascent of the fish. Computational methods
are developed to numerically obtain flow fields of the agricultural drainage system and then the ascending probability in
the entire spatio-temporal domain. The values of model parameters are deductively inferred, referring to results of field
observations. From the computational results of the ascending probability in the agricultural drainage system, effects of
hydraulic structures allowing ascent of the fish are clarified. 相似文献
85.
Junichiro Takeuchi Chie Imagawa Toshihiko Kawachi Koichi Unami Shigeya Maeda Tomoki Izumi 《Paddy and Water Environment》2010,8(2):175-187
A distributed hydro-environmental model is developed that achieves detailed analysis of the movement of water at a field-plot-scale
resolution in a mesoscale watershed including lowland areas where, especially for agricultures, it is an essential need to
get rid of redundant groundwater by drainage facilities such as rivers, canals and/or underdrains. For this, the problem geometry
is meshed with unstructured cells of triangular shape. Profile of a column cell is zoned into two: surface zone and groundwater
zone in which water movement is represented by combined tank and soil moisture sub-models, and well-defined two-dimensional
unconfined shallow groundwater flow sub-model, respectively. The top-two sub-models serve to evaluate evapotranspiration,
infiltration, soil water content, lateral surface water flow, and vertical percolation. The vertical percolation so evaluated
is given as longitudinal recharge to the bottom sub-model for computing groundwater flow. Surface water–groundwater interactions
through beds and stream-banks of perennial and ephemeral canals are considered by treating the canal courses as internal boundaries
in the groundwater flow model. The finite volume method (FVM) that allows of unstructured mesh and produces conservative solutions
is employed for groundwater flow computation. The model developed is applied to an actual watershed which includes a low-lying
paddy area to quantify the hydrological impact of land-use management practices over a period of 29 years in which the farmland
consolidation project was implemented and part of the paddy fields were converted to upland crop fields and housing lands.
From the results obtained, it is concluded that the model presently developed lends itself to water—as well as land-use management
practices. 相似文献
86.
Chie Imagawa Junichiro Takeuchi Toshihiko Kawachi Kei Ishida Shunsuke Chono Natsuki Buma 《Paddy and Water Environment》2011,9(4):425-439
Long-term simulation using the distributed hydro-environmental watershed model is efficacious for assessing irrigation impacts
on hydrological cycle in detail and for implementing watershed management successfully. In this article, the previously developed
hydro-environmental watershed model (HEWM-1) is improved in the water exchange process caused by surface water-groundwater
interaction via drainage canals and/or underdrains. The time-varying stream flow in canals is described by the complete one-dimensional
shallow water equations in a newly introduced submodel, the open channel flow submodel. This submodel coordinates with the
other submodels: the tank, soil moisture and groundwater flow submodels which are interlinked in a cascade manner. The improved
model (HEWM-2) is applied to an agricultural watershed covering an area from an alluvial fan onto a nearly level alluvial
plain, to be validated. The simulation by HEWM-2 is informative for identifying whether any drainage canal is gaining or losing
water in relation to groundwater level. It could thus provide useful information for conserving a complex network of drainage
canals which also functions as a passage for aquatic animals like fishes. 相似文献
87.
Hiroe Yoshida Kunihiko Takehisa Toshihiko Kojima Hiroyuki Ohno Kaori Sasaki 《Plant Production Science》2016,19(1):30-42
The objective of this study was to propose a model for explaining rice responses to a wide range of N application rates in various growth attributes associated with the occurrence of chalky grains. We improved the sub-model for N uptake process of a previous rice model which was originally developed for explaining genotypic and environmental variations in the whole growth processes, considering the difference in the rate of N loss from the plant-soil system between indigenously supplied soil mineral N and fertilizer N. A total of 80 growth datasets of cultivar ‘Koshihikari’ grown at Shiga prefecture, Japan, in 2010 was utilized for the calibration and validation of the model. The rice growth model well explained the above-ground biomass growth (RMSD = 78.7 g m?2) and rough dry grain yield (RMSD = 83.2 g m?2) for the validation data-set, simultaneously. The simulated carbohydrate content available per single spikelet was negatively correlated with the observed percentage of the milky-white grain which includes white-cored grain (r = ?.77, p < .001) for all the data-sets of calibration and validation. On the other hand, the observed percentage of the sum of white-back and white-base grains was closely correlated with the simulated plant N content available per single spikelet (r = ?.59, p < .001). It was suggested that the present rice growth model would rationally explain the effects of N application on the occurrence of the chalky grains through the dynamic change of the carbohydrate content and plant N content available per single spikelet. 相似文献
88.
The present study aimed to know whether all cows have been showing declining fertility or only a proportion of cows are attributed to the declining fertility, and to describe factors affecting the level of fertility. A total of 131 cows calved from February 2005 to December 2007 in a dairy herd were examined. Fourteen cows were excluded from the study because of early culling. Of the remaining 117 cows, 47 (40%) conceived within 115 days postpartum after 1–3 artificial insemination (AI) (normal fertility cows), 42 (36%) conceived after 115 days postpartum following 1–3 AI or were culled after 1–2 (sub‐fertility cows/culled), and 28 (24%) were inseminated more than three times without detectable genital tract abnormalities (repeat breeders). Calving to conception interval in the normal fertility group was 72 + 3 days, while in the sub‐fertility/culled and repeat breeding groups the intervals were 170 + 8 and 259 + 16 days, respectively. Endometritis was the risk factor for sub‐fertility/culled (odds ratio (OR) = 3.76). Prolonged luteal phase (OR = 4.08), delayed first ovulation (OR = 6.02), and delayed corpus luteum formation after AI (OR = 8.55) were the risk factors for repeat breeding. In conclusion, 60% cows showed reduced fertility in a herd, while the other 40% had normal fertility. Uterine infection and some ovarian disorders contributed to reduced fertility. 相似文献
89.
Akihiro MATSUURA Masaya TANAKA Mami IRIMAJIRI Atusi YAMAZAKI Toshihiko NAKANOWATARI Koichi HODATE 《Animal Science Journal》2010,81(5):618-621
Horse trekking (HT) is having a stroll on a horse along a walking trail in a forest, field, and/or sandy beach. Generally in HT, horses exercise in tandem line outside the riding facilities. Because the leading horse will be confronted with stressors in the forefront, we hypothesized that the leading horse shows higher stress responses than the following one. In order to verify the hypothesis, we compared short‐term stress responses between each position in six horses. Exercise consisted of 15 min of ground riding and 45 min of HT with walking and trotting. Heart rate variability was analyzed for 5 min at 30, 60, and 90 min after the exercising period. There was no significant difference in heart rate during exercise between leading and following positions. The high frequency / low frequency power band of heart rate variability, an index of sympathetic nervous activity, after exercise, tended to be higher in the leading position than following one (P < 0.1). The result in this study can suggest that the leading horse was in a higher stressed state than the following horse after HT. 相似文献
90.
Takuya Kubo Tsuyoshi Kobayashi Kyoko Kato Seiichi Nishimura Shigeru Uemura Kiyomi Ono Akihiro Sumida Toshihiko Hara 《Agricultural and Forest Meteorology》2008,148(8-9):1293-1304
In order to more accurately evaluate the functional activity of forest stands by canopy production and evapotranspiration, we improved the methods for field measurements and statistical modeling to estimate foliage configuration (spatial distribution of leaves) while simultaneously reconstructing the three-dimensional photosynthetically active photon flux density (PPFD) distribution (PPFD pattern) in a forest canopy. By using a sensor (photodiode) array, a PPFD pattern was observed in summer 2002 under the canopy in an even-aged, pure stand of Japanese mountain birch Betula ermanii Cham. (17-years old) in Hokkaido, northern Japan. A Markov chain Monte Carlo (MCMC) sampling technique is developed such that a set of foliage configurations generated by the model referred to as the Gibbs foliage canopy (GFC) approximates the field-measured PPFD pattern. The posterior distribution of the foliage configurations is generated by the parallel tempering MCMC of eight independent series of foliage configurations. The GFC model generated the posterior distribution of the LAI estimates (mean 4.56) that appeared to be appropriate in comparison to other LAI estimates of the B. ermanii stand based on the indirect and nondestructive methods by LAI-2000 (LAI = 3.43) and litterfall traps (LAI = 5.56) because they could be under- and overestimated, respectively. Our evaluations of the canopy production and evapotranspiration rates suggest that the relationship between LAI and canopy functions was not very simple because it depended on the nonlinear functional forms of the leaf responses of photosynthesis and transpiration to PPFD. The current study demonstrates an application of MCMC techniques that can generate a set of possible structures of unobserved/unobservable objects based on the high-resolution dataset obtained by some indirect (or remote-sensing) methods. 相似文献