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Hikone, Japan

The University of Shiga Prefecture is a public university in Hikone, Shiga, Japan. The predecessor of the school was founded in 1950, and it was chartered as a university in 1995. Wikipedia.

Wheat is one of the most important cereal crops for human consumption. Understanding the eco-efficiency of wheat production is helpful in achieving sustainable agriculture. In this study, the eco-efficiency of wheat production in Japan at a regional scale was measured using a combined methodology of life cycle assessment and data envelopment analysis. Wheat production in paddy fields with inferior drainage performance was compared with production in upland fields with good growing conditions. The eco-efficiency indicator was defined as wheat yield per single environmental impact index, including global warming as a global environmental category and aquatic eutrophication as a regional one. The results indicate that eco-efficient wheat production can occur in both good and poor growing conditions, with a wheat yield obtained by an adequate application of nitrogen fertilizer. The mitigation of aquatic eutrophication caused by the excessive use of nitrogen fertilizer is an important factor in improving the eco-efficiency of wheat production. © 2016 Elsevier Ltd. Source

Noriyuki S.,Kyoto University | Osawa N.,Kyoto University | Nishida T.,University of Shiga Prefecture
Journal of Animal Ecology | Year: 2012

Closely related species often differ greatly in the quality and breadth of resources exploited, but the actual mechanisms causing these differences are poorly understood. Because in the laboratory specialized species often survive and perform as well or better on host species that are never utilized in nature, negative ecological interactions restricting host range must exist. Here, we focused on reproductive interference, which has been theoretically predicted to drive niche separation between closely related species with overlapping mating signals. We examined the interspecific sexual interactions in relation to ecological specialization and generalization in two sibling ladybird species, Harmonia yedoensis and Harmonia axyridis. Harmonia yedoensis is a specialist predator that preys only on pine aphids, which are highly elusive prey for ladybird hatchlings, whereas H. axyridis is a generalist predator with a broad prey and habitat range. We experimentally showed that conspecific sperm fertilized the vast majority of eggs regardless of mating order (i.e. conspecific sperm precedence) when a female of H. yedoensis or H. axyridis mated with both a conspecific and a heterospecific male. Moreover, we demonstrated that mating opportunities of H. yedoensis females strongly decreased as heterospecific density increased relative to conspecific density. In contrast, in H. axyridis, female mating success was high regardless of conspecific or heterospecific density. Our results suggest that the generalist H. axyridis should be dominant to the specialist H. yedoensis in terms of reproductive interference. Our results support the hypothesis that asymmetric reproductive interference from the dominant species may force the non-dominant species to become a specialist predator that exclusively utilizes less preferred prey in nature. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society. Source

We demonstrate that circular polariscopy is highly sensitive to strains in SiC wafers. In the monochromatic x-ray topographic analysis, which is regarded as a fundamental characterization method, the image information is disappeared in various areas: x-ray topography is not always suitable to evaluate wafer-size regions. Using circular polarizer plates, we apply the polariscopic analysis, which reveals the inhomogeneous strain distributed in the whole wafer region; namely, the circular polariscopic map has the high potential to complement the conventional monochromatic x-ray topograph. From the phonon-frequency shift observed in the Raman scattering spectra, the maximum stress is estimated to be ∼490 MPa. The crystal-plane distortion causing the strains is confirmed from the appearance of the forbidden reflections in the θ-2θ x-ray diffraction pattern. © 2011 American Institute of Physics. Source

Hatanaka Y.,University of Shiga Prefecture
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference | Year: 2011

Retinal image examination is useful for early detection of glaucoma, which is a leading cause of permanent blindness. In order to evaluate the presence of glaucoma, ophthalmologists may determine the cup and disc areas and diagnose glaucoma using a vertical cup-to-disc ratio. However, determination of the cup area based on computation algorithm is very difficult, thus we propose a method to measure the cup-to-disc ratio using a vertical profile on the optic disc. The edge of optic disc was then detected by use of a Canny edge detection filter. The profile was then obtained around the center of the optic disc. Subsequently, the edges of the cup area were determined by classification of the profiles based on zero-crossing method. Lastly, the vertical cup-to-disc ratio was calculated. Using forty five images, including twenty three glaucoma images, the AUC of 0.947 was achieved with this method. Source

Kyogoku D.,Kyoto University | Nishida T.,University of Shiga Prefecture
Population Ecology | Year: 2013

Male promiscuity sometimes results in interspecific reproductive interaction, also known as reproductive interference. Reproductive interference entails costs for the individuals involved and affects the community structure by reducing the population growth rate. However, our understanding of the mechanisms generating reproductive interference is still insufficient. Two congeneric bean weevils, Callosobruchus chinensis and C. maculatus, show asymmetric reproductive interference; only C. chinensis males reduce the fecundity of the other species. Here we investigated the mechanism of reproductive interference by C. chinensis males on C. maculatus females in terms of lifetime fecundity. Callosobruchus chinensis males with ablated genitals, which could harass C. maculatus females but not copulate with them, did not reduce the C. maculatus fecundity, suggesting that interspecific copulation was necessary. However, a single interspecific copulation did not affect C. maculatus fecundity as long as the females also copulated with a conspecific male. Exposure to C. chinensis males for 24 h prior to oviposition significantly reduced C. maculatus fecundity, and fecundity was negatively correlated with the number of C. chinensis males the females were exposed to. Additionally, C. maculatus females experienced more interspecific copulations when they were housed with more C. chinensis males. Together these findings suggest that multiple interspecific copulations by C. chinensis males reduce the fecundity of C. maculatus females. Thus in general, even if a single interspecific copulation is apparently harmless, repeated interspecific copulations can be costly for the individuals involved. Furthermore, only by quantifying reproductive success were we able to identify the precise mechanism of reproductive interference. © 2012 The Society of Population Ecology and Springer Japan. Source

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