Age-dependent walking and feeding of the assassin bug Amphibolus venator

Animal behaviours often dependent on age. In many insect species, walking shows an age-dependent decline, and food intake may also be dependent on age. However, few studies have investigated the relationship between age and walking or food intake. In the present study, we compared walking traits and food intake among individuals of different ages in the assassin bug Amphibolus venator (Hemiptera, Reduviidae). The present results showed an age-dependent decline in walking, similar to findings in many animal species. On the other hand, food intake showed a positive correlation with age. Therefore, the decline in walking did not lead to a decline in feeding. The positive relationship between food intake and age may be related to the type of predation, sit-and-wait, used by A. venator via alterations in investment in reproductive traits with age

Arousal from Tonic Immobility by Vibration Stimulus

Tonic immobility (TI) is an effective anti-predator strategy. However, long immobility status on the ground increases the risk of being eaten by predators, and thus insects must rouse themselves when appropriate stimulation is provided. Here, the strength of vibration causing arousal from the state of TI was examined in strains artificially selected for longer duration of TI (L-strains: long sleeper) in a beetle. We provided different strengths of vibration stimuli to the long sleepers in Tribolium castaneum. Although immobilized beetles were never awakened by the stimuli from 0.01 to 0.12 mm in amplitude, almost of the beetles were aroused from immobilized status by the stimulus at 0.21 mm. There was a difference in sensitivity of individuals when the stimuli of 0.14 mm and 0.18 mm were provided. F2 individuals were also bred by crossing experiments of the strains selected for shorter and longer duration of TI. The arousal sensitivity to vibration was well separated in the F2 individuals. A positive relationship was observed between the duration of TI and the vibration amplitude, suggesting that immobilized beetles are difficult to arouse from a deep sleep, while light sleepers are easily aroused by even small vibrations. The results indicate a genetic basis for sensitivity to arousal from TI

Robot Motion Generation by Hand Demonstration

Since traditional robot teaching requires time and instruction to the robot motion, we present a systematic framework based on deep learning and experiment for generating robot motion trajectories from human hand demonstration. In this system, the worker could teach robot easier rather than assigning the instruction to the robot controller manually. Therefore, the robot can imitate the action in a new situation instead of directly teaching the robot arm. Our contributions include three points 1) the real-time extracting method of hand movement without marker using hand detection in 3D from human 2) the motion generalization of the hand trajectories from human 3) Robot path planning for grasping and place the object to the target. We also present the experiment conducted by the user movement for real data and evaluate the system using the manipulator robot. The investigation shows the pick-and-place task of the robot for food by hand demonstration.The 2021 International Conference on Artificial Life and Robotics (ICAROB 2021), January 21-24, 2021, Higashi-Hiroshima (オンライン開催に変更

Arousal from death feigning by vibrational stimuli: comparison of Tribolium species

Death feigning (or tonic immobility) is an effective antipredator strategy. However, prolonged immobility on the ground increases the risk of being parasitized or eaten by predators, and thus, insects must rouse themselves when appropriate stimulation is provided. Very few studies on the effect of stimulus intensity on arousal from death feigning have been conducted. A previous study using Tribolium castaneum showed an existing threshold for the intensity of the stimulus that causes arousal from death feigning. Whether there are differences between species in the threshold for arousal is an interesting question. In the present study, we, therefore, compared the effect of stimulus strength on arousal from death feigning in two closely related species, namely, T. confusum and T. freemani, which are established strains that have been artificially selected for longer duration of death feigning. Also, part of the study was to determine whether there was a positive association between intensity of stimulus needed to rouse and the duration of death feigning. We discuss why there is a difference in the strength of the stimulus needed for arousal from death feigning among Tribolium species, for which we included the data for T. castaneum from a previous study

Development of LiDAR Based Navigation System for Automation of Tree Harvesting Process

This study focuses on an autonomous moving system for the automation of the harvesting process by high-performance machines in the forestry. Many fatal accidents occur due to the harvesting process. In this research, a navigation system has been developed to enable autonomous travel between accumulation sites and trees to be harvested to improve productivity and safety. A 3D map is generated by LiDAR observation, and harvester moves autonomously towards the tree as specified by the operator. A test of the harvesting process was performed in an experimental environment. The evaluation focused on the required time of the autonomous movement in the process. The effectiveness of the system was confirmed in operations such as row thinning by the results.The 2021 International Conference on Artificial Life and Robotics (ICAROB 2021), January 21-24, 2021, Higashi-Hiroshima (オンライン開催に変更

Improved Variational Autoencoder Anomaly Detection in Time Series Data

Uncertainty in observations about the state of affairs is unavoidable, and generally undesirable, so we are motivated to try to minimize its effect on data analysis. Detection of anomalies in data has become an important research area. In this paper, we propose a novel approach to anomaly detection based on the Variational Autoencoder method with a Mish activation function and a Negative Log-Likelihood loss function. The proposed method is validated with ten standard datasets, comparing performance on each of the various activation functions and loss functions. Experimental results show that our proposed method offers an improvement over existing methods. Statistical properties (i.e., F1 score, AUC, and ROC) of the method are also examined in light of the experimental results.2020 IEEE International Conference on Systems, Man, and Cybernetics (SMC 2020), October 11-14, 2020, Toronto, Canada （オンライン開催に変更

Affixin interacts with α-actinin and mediates integrin signaling for reorganization of F-actin induced by initial cell–substrate interaction

The linking of integrin to cytoskeleton is a critical event for an effective cell migration. Previously, we have reported that a novel integrin-linked kinase (ILK)–binding protein, affixin, is closely involved in the linkage between integrin and cytoskeleton in combination with ILK. In the present work, we demonstrated that the second calponin homology domain of affixin directly interacts with α-actinin in an ILK kinase activity–dependent manner, suggesting that integrin–ILK signaling evoked by substrate adhesion induces affixin–α-actinin interaction. The overexpression of a peptide corresponding to the α-actinin–binding site of affixin as well as the knockdown of endogenous affixin by small interference RNA resulted in the blockade of cell spreading. Time-lapse observation revealed that in both experiments cells were round with small peripheral blebs and failed to develop lamellipodia, suggesting that the ILK–affixin complex serves as an integrin-anchoring site for α-actinin and thereby mediates integrin signaling to α-actinin, which has been shown to play a critical role in actin polymerization at focal adhesions