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We investigated the effect of attention on the flash-lag effect (FLE) in order to determine whether the FLE can be used to estimate the effect of visual attention. The FLE is the effect that a flash aligned with a moving object is perceived to lag the moving object, and several studies have shown that attention reduces its magnitude. We measured the FLE as a function of the number or speed of moving objects. The results showed that the effect of cueing, which we attributed the effect of attention, on the FLE increased monotonically with the number or the speed of the objects. This suggests that the amount of attention can be estimated by measuring the FLE, assuming that more amount of attention is required for a larger number or faster speed of objects to attend. On the basis of this presumption, we attempted to measure the spatial spread of visual attention by FLE measurements. The estimated spatial spreads were similar to those estimated by other experimental methods.

Statistical properties of position-dependent ball-passing networks in real football games are examined. We find that the networks have the small-world property, and their degree distributions are fitted well by a truncated gamma distribution function. In order to reproduce these properties of networks, a model based on a Markov chain is proposed.

The results of the model reactions with ethanol or 2-propanethiol and acetic acid showed that the dehydration condensation of the ethanol reaction was chemoselective and that thioesterification did not occur under the conditions used. We synthesized polyesters with pendant mercapto groups by dehydration polycondensations of diols and TMA, and as with the model reactions, esterification proceeded chemoselectively and thioesterification did not occur. The pendant mercapto-containing polyesters had M ns >1.0 × 104. We also demonstrated that the pendant mercapto groups could be chemically modified by glycosylation or cross-linked by TCDI to synthesize a gelatinous RAFT agent as a first example, which acted as a RAFT agent in a radical polymerization to afford poly(methyl methacrylate) with a narrow molecular weight distribution (M n = 8.5 × 104, M w/M n = 1.47). These procedures could be used to produce new types of polyesters from monomers that differ in chirality and functionality and also nanoscale-reactive media containing RAFT agent as a cross-linker for controlled radical polymerization of vinyl monomers.

To examine whether visual attention shifts continuously across the visual field, we measured sensitivity to a small flash presented at various locations while the observer was tracking a moving target in an ambiguous apparent motion display. The sensitivity peaked near the target and the peak shifted smoothly along the apparent motion path. Since the peak-shift speed varied with the speed of the tracked target, we conclude that the attention mechanism selects the location to facilitate processing by tracking the target disk continuously. Attention does not simply select a location for enhanced processing, but rather predicts the future location of the object of interest based on its velocity.

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Asymptotic analysis on some statistical properties of the random binary-tree model is developed. We quantify a hierarchical structure of branching patterns based on the Horton-Strahler analysis. We introduce a transformation of a binary tree, and derive a recursive equation about branch orders. As an application of the analysis, topological selfsimilarity and its generalization is proved in an asymptotic sense. Also, some important examples are presented.