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Biology subjects

Anzai, H.

Publications and source records attributed to Anzai, H..

2 recordsLinked to original sources

Animal-robot interaction in the field: stronger responses and slower habituation of grazing cattle to a quadruped robot than to a drone

Robotic herding offers a promising off-animal approach to controlling the spatial distribution of grazing livestock. Nevertheless, the habituation of cattle to herding stimuli remains a critical obstacle to its practical use. This study presents the first field investigation of behavioral responses of grazing cattle to herding by a quadruped robot. We compared the herding efficacy of a drone and a quadruped robot, and tracked daily changes in responsiveness during continuous herding. Trials were conducted in a 1.1-ha pasture with Japanese Black breeding cows from June to October 2023. The quadruped robot elicited stronger avoidance responses with shorter latencies than the drone, and herding was more successful with the robot. During consecutive daily herding with the robot, behavioral responsiveness declined progressively over the initial 5 days, at a markedly slower rate than previously reported for drone herding. Following a 24-day interruption, responsiveness partially increased, but declined rapidly again over the subsequent two days. These results indicate that the quadruped robot constitutes a more persistent aversive stimulus than a drone for grazing cattle, although habituation management strategies (such as diversifying stimuli or combining sensory modalities) will be necessary for sustained control of grazing distribution.

animal behavior and cognition↗

Comparing the Effect of Helical-centerline Stent Placement on Blood Flow Velocity with a Straight Stent

Stent treatment can be used to treat blood vessel stenosis in a less invasive manner, but re-stenosis is a concern. Because a helical-stent configuration has been thought to reduce the amount of intimal hyperplasia, the helical stent is considered clinically effective. The effects of the helical stent on blood flow velocity, however, have not been studied. In this study, we estimated flow velocities before and after helical stenting using time-intensity-curve (TIC) from angiography images and compared them with straight stenting velocities. As a result, in all cases (N = 3), the velocity reduction was less with helical stenting than with straight stenting. Based on angiography images, this flow estimation method can estimate patient-specific blood flow velocity in situ even in a presence of a stent.

bioengineering↗