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51.
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   
52.
We aimed to determine the effectiveness of estrus detection based on continuous measurements of the ventral tail base surface temperature (ST) with supervised machine learning in cattle. ST data were obtained through 51 estrus cycles on 11 female cattle (six Holsteins and five Japanese Blacks) using the tail-attached sensor. Three estrus detection models were constructed with the training data (n = 17) using machine learning techniques (random forest, artificial neural network, and support vector machine) based on 13 features extracted from sensing data (indicative of estrus-associated ST changes). Estrus detection abilities of the three models on test data (n = 34) were not statistically different among models in terms of sensitivity and precision (range 50.0% to 58.8% and 60.6% to 73.1%, respectively). The relatively poor performance of the models might indicate the difficulty of separating estrus-associated ST changes from estrus-independent fluctuations in ST.  相似文献   
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Resistance to soybean mosaic virus (SMV) is imperative for soybean (Glycine max (L.) Merr.) production in the Tohoku region. Molecular markers for SMV resistance were previously reported for U.S. SMV strains, but they cannot be applied because of the differences in strain classification between Japan and the U.S. A U.S. variety ‘Harosoy’ has been used mainly as a donor of resistance to SMV strains C and D in a Japanese breeding program, resulting in resistant varieties such as ‘Fukuibuki.’ Because ‘Harosoy’ harbors the Rsv3 gene conferring resistance to the virulent SMV strain groups, G5 through G7, it appears that the Rsv3 gene confers resistance to strains C and D. In this study, we introduced resistance to the two strains from ‘Fukuibuki’ into a leading variety ‘Ohsuzu’ by recurrent backcrossing with marker-assisted selection. All lines selected with markers near Rsv3 showed resistance to the strains, suggesting that the Rsv3 locus is responsible for the resistance. Three years of trials showed that one of the breeding lines, ‘Tohoku 169,’ was equivalent to ‘Ohsuzu’ with respect to agricultural characteristics such as seed size, maturity date, and seed yield, except for the SMV resistance.  相似文献   
55.
Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs.  相似文献   
56.
The peanut stunt virus (PSV) causes yield losses in soybean and reduced seed quality due to seed mottling. The objectives of this study were to determine the phenotypic reactions of soybean germplasms to inoculation with two PSV isolates (PSV-K, PSV-T), the inheritance of PSV resistance in soybean cultivars, and the locus of the PSV resistance gene. We investigated the PSV resistance of 132 soybean cultivars to both PSV isolates; of these, 73 cultivars exhibited resistance to both PSV isolates. Three resistant cultivars (Harosoy, Tsurunotamago 1 and Hyuga) were crossed with the susceptible cultivar Enrei. The crosses were evaluated in the F1, F2 and F2:3 generations for their reactions to inoculation with the two PSV isolates. In an allelism test, we crossed Harosoy and Tsurunotamago 1 with the resistant cultivar Hyuga. The results revealed that PSV resistance in these cultivars is controlled by a single dominant gene at the same locus. We have proposed Rpsv1, as the name of the resistance gene in Hyuga. We also constructed a linkage map using recombinant inbred lines between Hyuga × Enrei using 176 SSR markers. We mapped Rpsv1 near the Satt435 locus on soybean chromosome 7.  相似文献   
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The db/db mouse is one of the diabetes mellitus animal models and if the pathophysiological stages of diabetic changes in the mouse model could simulate the stages in human diabetes, the db/db mouse could be used to better evaluate drug candidates. Blood insulin, HbA1c levels and morphological features of pancreatic islets in db/db mice were evaluated to determine the pathophysiological stage. At 6 weeks of age, db/db mice showed the highest level of plasma insulin and lowest level of HbA1c, and histopathological examination revealed enlarged islets with a circular shape and hypertrophic islet cells. By 9 and 12 weeks of age, the plasma insulin levels had decreased to mid levels and HbA1c had increased to mid to high levels; histopathological examination at this time revealed two types of islets coexisting, enlarged circular islets and small irregular-shaped islets. By 15 and 22 weeks of age, plasma insulin had decreased further to low levels and HbA1c was at its highest level; the histopathological examination at this time revealed an increase in irregular-shaped and small islets. Based on blood insulin levels, HbA1c levels and histopathology findings in the db/db mice in this study, the clinical staging of diabetic changes were recognized. The pathophysiological stages of diabetes mellitus in this animal model were similar to the stages in humans.  相似文献   
59.
Soybean ( Glycine max ) cv. Harosoy 63 is resistant to race 1 and susceptible to race 9 of Phytophthora megasperma f. sp. glycinea (Pmg). In detached primary leaves inoculated with zoospores, growth of race 1 was completely suppressed 16 h after inoculation, while race 9 was unaffected. The amount of the phytoalexin glyceollin that accumulated, however, was not significantly different in either the incompatible or compatible interaction 16 h after inoculation. At the circumference of the inoculated area, a slight accumulation of phytoalexin was observed only in the incompatible interaction 20 h or more after inoculation. Tolerance of race 9 to the phytoalexin was significantly higher than that of race 1 when the phytoalexin was added to agar. Moreover, race 9 degraded glyceollin faster than race 1. On leaves inoculated at separate points with either race, the lesion associated with race 9 never colonized areas inoculated with race 1. These results suggest that factor(s) other than the accumulation of phytoalexin in soybean tissue might cause cessation of growth of Pmg.  相似文献   
60.
Glutamate decarboxylase (GAD) is the primary enzyme in the brain that catalyzes the synthesis of gamma-aminobutyric acid (GABA), the main inhibitory neurotransmitter. There are two isoforms named according to their molecular weights, GAD67 and GAD65, which are encoded by GAD1 and GAD2, respectively. To investigate the association between GAD genes and temperament in domestic dogs, Canis familiaris, we sequenced the full lengths of the coding regions of these genes and identified three single nucleotide polymorphisms (SNPs) in GAD1 and one in GAD2. When comparing genotype and allele frequencies of SNPs among five breeds with different behavioral traits, statistically significant interbreed differences were observed for three SNPs in GAD1. These results suggest that GAD1 SNPs may be useful for behavioral genetic studies in dogs.  相似文献   
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