Recently, fish ways have been set at the floodgate for most of the rivers in Japan to maintain aquatic ecosystems. Fish ways are demonstrated to be effective for larger size fish to pass the floodgate for running up the river, however, quantitative information is very limited and has not been obtained for smaller size fish. This study was designed to develop an automatically fish counting system for the fish way with line imaging sensors.

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The present work investigates alternative meanings of dynamic sensitivities in steady state by using two metabolic reaction models. The calculated results clearly show that the dynamic sensitivity values given from a change in an independent variable such as an enzyme activity correspond to a step response, while those given from a change in a dependent variable such as a metabolite concentration correspond to an impulse response. They also indicate that the time-transient behavior of the propagation of a perturbation can efficiently elucidate the characteristics of network structure.

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To examine the factors influencing the formation of plant zonation in a brackish marsh, vegetation and soil characteristics were investigated at 5-m intervals from the shore of the brackish Lake Obuchi, located in northern Japan. Two-way indicator species analysis (TWINSPAN) broadly classified the sites into Phragmites australis-dominated, Juncus yokoscensis-dominated, and Miscanthus sinensis and Cirsium inundatum-dominated vegetations. Vegetation boundaries were distinct and the order of vegetation arrangement corresponded with the distance from the shore of Lake Obuchi, which indicated the existence of plant zonation. Species diversity increased in the order of P. australis-dominated < J. yokoscensis-dominated < M. sinensis and C. inundatum-dominated vegetation. Electrical conductivity (salinity index) in the soil was the highest in P. australis-dominated vegetation. Inorganic N conc entration in the soil tended to increase in the order of P. australis-dominated < J. yokoscensis-dominated < M. sinensis and C. inundatum-dominated vegetation. These results suggest that, concerning on the zonation around the brackish Lake Obuchi, species distributions in the area nearer to the shore are determined by tolerance to salinity.

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In closed ecological life support systems such as the International Space Station (ISS), the atmosphere and water are continuously recirculated, and the risk of infection increases when bacteria survive and proliferate. Microbial monitoring is important to assure the health and safety of staffs who live in these environments for extended periods. Swab method is currently used for microbial monitoring in the ISS, but the inter-operator variation is high because the protocol is not standardized and staff members without microbiological background must perform the sampling procedures. Here, we describe a simple swab procedure with higher operability and fewer individual differences than current methods. Concretely, we adopted the technique to swab one-way horizontally and vertically on the surface every cm without changing the contact face of the swab. Culture-independent fluorescence microscopy was used to count microbial cells for more accurate monitoring. Our protocol is simple and reliable, and it should be useful for microbial monitoring in the ISS.

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A strawberry grading and sorting system used for cooperative farmers was developed to reduce time and labor in processing. It consists of weight measuring units, a non-destructive quality analyzer which uses near infrared rays to measure sugar and acid content in strawberry, pans carrying strawberries, and conveyors transporting them. The quality analyzer predicts sugar content with a higher level of accuracy than the SEP 0.5 brix%.

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