Visual image of neighbors to elicit wandering behavior in the soldier crab

The soldier crab appears in great numbers and feeds while wandering during daytime low tide. When they see an approaching object, they screw themselves into the sand. The mechanism of formation of mass wandering has not been clarified. In this study, to investigate if the soldier crabs use visual images of neighbors as a stimulus for wandering, dummy crabs were presented to crabs. In the experiments, one, two, four, or eight dummies were placed in a circle on a sand arena. Each crab was placed in the center of the arena and observed whether it burrowed into the sand or wandered. The proportions of wandering individuals in each experimental treatment were compared with the expected value. Significantly more crabs were wanderers when only two and four dummies were present. This result suggests that soldier crabs chose burrowing or wandering depending on visual image of the distribution of the neighbors.     

A control law for vehicle merging inspired by dragonfly behavior

Autonomous control of vehicles has recently attracted considerable attention. In this sense, vehicle merging has become an important topic in this field of research. However, in conventional studies, the controlled vehicle must calculate the movement of other surrounding vehicles to complete the merge, requiring high computational costs. In this paper, we focus on dragonfly behavior to solve this issue. Indeed, insects can behave adaptively in the complex real world in spite of the limited size of their brains. They reduce the computational requirements of their brain by relying on different properties of their surroundings, basing their intelligent behaviors on simple strategies. The behavior of a dragonfly when chasing a prey is an example of these strategies. In this study, we address the vehicle merging maneuver by applying dragonfly’s strategies to control the movement of the merging vehicle. We propose a simple control method inspired by the aforementioned strategies and, finally, we present simulation results that were conducted to demonstrate the effectiveness of this method.     

Chiral lewis acid-catalyzed enantioselective michael reactions in water

Asymmetric Michael reactions of ß-ketoesters with enones were effectively catalyzed by complexes of silver salts and BINAP derivatives in water. The reactions have proved to give Michael adducts in high yields with high enantioselectivities. These reactions are the first example of Lewis acid-catalyzed asymmetric Michael reactions in water.     

Adaptive dynamic range shift (ADRIFT) quantitative phase imaging

Quantitative phase imaging(QPI)with its high-contrast images of optical phase delay(OPD)maps is often used for label-free single-cell analysis.Contrary to other imaging methods,sensitivity improvement has not been intensively explored because conventional QPI is sensitive enough to observe the surface roughness of a substrate that restricts the minimum measurable OPD.However,emerging QPI techniques that utilize,for example,differential image analysis of consecutive temporal frames,such as mid-infrared photothermal QPI,mitigate the minimum OPD limit by decoupling the static OPD contribution and allow measurement of much smaller OPDs.Here,we propose and demonstrate supersensitive QPI with an expanded dynamic range.It is enabled by adaptive dynamic range shift through a combination of wavefront shaping and dark-field QPI techniques.As a proof-of-concept demonstration,we show dynamic range expansion(sensitivity improvement)of QPI by a factor of 6.6 and its utility in improving the sensitivity of mid-infrared photothermal QPI.This technique can also be applied for wide-field scattering imaging of dynamically changing nanoscale objects inside and outside a biological cell without losing global cellular morphological image information.