Fumiki Takahashi

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1. A computational model accounting for motion detection in the fly was examined by comparing responses in motion-sensitive horizontal system (HS) and centrifugal horizontal (CH) cells in the fly's lobula plate with a computer simulation implemented on a motion detector of the correlation type, the Reichardt detector. First-order (linear) and second-order(More)
Chemical components stimulating oviposition bySitophilus zeamais in rice grain were isolated from rice bran and were found to be a mixture of ferulates, diglycerides, and free sterols. Oviposition preference of the species can be induced by synergistic action of these compounds.
An educational use of Pepper, a personal robot that was developed by SoftBank Robotics Corp. and Aldebaran Robotics SAS, is described. Applying the two concepts of carereceiving robot (CRR) and total physical response (TPR) into the design of an educational application using Pepper, we offer a scenario in which children learn together with Pepper at their(More)
This paper reports on a rapid and sensitive method for the simultaneous determination of ascorbic acid (H(2)A), dehydroascorbic acid (DHA), and total vitamin C by electrochemiluminescence (ECL) using a thin-layer electrochemical cell. Significant ECL signals can be generated by the anodic oxidation of Ru(bpy)(3) (2+) in the presence of H(2)A or DHA in pH(More)
The regulation mechanism of insect population is considered in this paper using a very simplified model of the reproduction curve which has two equilibrium points. In many insects each generation does not overlap in a population and appears periodically, and it seems more convenient to deal with the population fluctuation in the unit of generation. In this(More)
A heterogeneous life cycle of individuals in a population was examined on its adaptive significance to an unstable environmental condition. The trend of population growth was simulated by a simple mathematical model in which a part of population in a certain generation was carried over to the next generation without participating in the reproduction. With(More)
1. The functional response to, and preference for, the host density in a parasite were examined experimentally using an icheumon wasp,Exidechthis canescens, and its hostCadra cautella under controlled conditions. 2. Wasps were more active in host-searching at higher than lower host densities. Percent parasitism increased rapidly with initial increments in(More)
In order to determine trace choline in human urine, a flow injection analysis (FIA) system has been developed by coupling an enzyme reactor with an electrochemiluminescence (ECL) detector. The enzyme reactor is prepared by covalently immobilizing choline oxidase (ChOx) onto the aminopropyl-controlled pore glass beads, which are then carefully packed into a(More)
Field-grownPinus densiflora seedlings were inoculated withBursaphelenchus xylophilus and the incidence of pine wilt disease was analyzed with respect to the spatial relationships between pine seedlings and adjacent seedlings of other tree species in a pure pine stand and three stands mixed withAlnus sieboldiana, Sarothamus scoparius or naturally associated(More)
In this study, electrochemiluminescence (ECL) of Ru(bpy)3 (bpy = 2,2'-bipyridyl) using ascorbic acid (H2A) as co-reactant was investigated in an aqueous solution. When H2A was co-existed in a Ru(bpy)3 containing buffer solution, ECL peaks were observed at potential corresponding to oxidation of Ru(bpy)3, and the intensity was proportional to H2A(More)