Kinetic analysis of reverse transcriptase activity of bacterial family A DNA polymerases.

Some bacterial thermostable, wild-type or genetically engineered family A DNA polymerases have reverse transcriptase activity. However, difference in reverse transcriptase activities of family A DNA polymerases and retroviral reverse transcriptases (RTs) is unclear. In this study, comparative kinetic analysis was performed for the reverse transcriptase activities of the wild-type enzyme of family A DNA polymerase (M1pol(WT)) from Thermus thermophilus M1 and the variant enzyme of family A DNA polymerase (K4pol(L329A)), in which the mutation of Leu329→Ala is undertaken, from Thermotoga petrophila K4. In the incorporation of dTTP into poly(rA)-p(dT)(45), the reaction rates of K4pol(L329A) and M1pol(WT) exhibited a saturated profile of the Michaelis-Menten kinetics for dTTP concentrations but a substrate inhibition profile for poly(rA)-p(dT)(45) concentrations. In contrast, the reaction rates of Moloney murine leukemia virus (MMLV) RT exhibited saturated profiles for both dTTP and poly(rA)-p(dT)(45) concentrations. This suggests that high concentrations of DNA-primed RNA template decrease the efficiency of cDNA synthesis with bacterial family A DNA polymerases

Development of Remotely Operated Vehicle for Small-size Jellyfish Extermination and its Evaluation of Extermination Motion Control

In recent years, increase in the number of jellyfish has caused damage in the fishery and tourism industries. Therefore, the extermination work of jellyfish is being carried out by human hands. However, conventional methods for extermination are required a lot of time and manpower. In this paper, we propose a method for extermination work of jellyfish using underwater robot. Also, we introduce developed ROV type underwater robot, which is called J.E.N.O.S. (Jellyfish Extermination Nifty-robot for Ocean Sustentation), and its extermination motion control. The ROV is developed in consideration of the attitude control during the extermination operation. Because, the attitude, such as surge and pitch angle, of ROV becomes unstable when performing jellyfish extermination. Therefore, we equipped 8 thrusters to improve attitude stability during the jellyfish extermination. As a result, surge acceleration is reduced to about 30.0%, and pitch angle velocity is reduced to about 25.8%.The 2022 International Conference on Artificial Life and Robotics (ICAROB 2022), January 20-23, 2022, on line, Oita, Japa

A robotic vision system emulating fixational eye movements and retinal sampling

Recent studies on visual physiology have suggested that fixational eye movements contribute to the information processing function of the retina. In this study, we built a robotic vision system that emulates the characteristics of fixational eye movements and retinal sampling as an assistant tool for clarifying information processing through the collaboration of eye movements and neural circuits. The proposed robotic vision system consists of two galvanometers, a field-programmable gate array (FPGA) board, and a high-speed, high-resolution camera. We measured the frequency response of this robotic vision system, and the results showed that the system satisfied the requirements for emulating the frequency characteristics of biological eye movements. In addition, we generated command signals in the FPGA to emulate biological eye movements and confirmed the satisfactory operation of the system.The 2022 International Conference on Artificial Life and Robotics (ICAROB 2022), January 20-23, 2022, on line, Oita, Japa

Evaluation of Tomato Fruit Harvestability for Robotic Harvesting

Harvestability is a quantitative index of how easy tomato fruits are to harvest using a robot. Previous studies on tomato harvesting robots have focused on tomato fruit detection methods, harvesting mechanisms, harvesting success rates, and harvesting times. However, tomato fruit harvestability using robots has not been quantitatively assessed. In this paper, we propose a method for evaluating the tomato fruit harvestability using a tomato harvesting robot. We first evaluated the harvestability qualitatively, based on the results of harvesting experiments conducted in a tomato greenhouse. Harvestability was then quantitatively evaluated using a camera (hereinafter referred to as a hand camera) attached to an end-effector of the tomato harvesting robot developed. The hand camera consists of an RGB camera and a depth camera. The occlusion ratio of obstacles (stems, peduncles, and other fruits) to a target fruit is calculated using the RGB image and depth image acquired by the hand camera. The larger the occlusion ratio was, i.e., the more obstacles there were in front of the target fruit, the more difficult the target fruit was to harvest. Conversely, if the occlusion ratio is low, the harvestability is high. This study shows that the occlusion ratio is effective as a quantitative indicator of the tomato fruit harvestability.2021 IEEE/SICE International Symposium on System Integrations (SII), January 11 - 14, 2021, Iwaki, Fukushima, Japa

Tomato Harvesting in Greenhouse Considering the Effect of Sunlight

Tomato is one of the important fruit vegetables and most tomatoes are produced in the greenhouses, or large-scale farms, where the high temperature and humidity, and long harvest age force the farmer heavy works. To develop the tomato harvesting robot, many research issues exist such as manipulator design, end-effector design, collaborative behavior, artificial intelligence, motor control, image processing, target recognition and so on. For the operation in greenhouses, the recognition system with color constancy under sunlight is necessary. In the harvesting, tomatoes should be handled gently for less damages so that the soft handling end-effector is needed. In this paper, we introduce the system configuration of the robot and the experiments conducted to solve the problem in the greenhouse.The 2022 International Conference on Artificial Life and Robotics (ICAROB 2022), January 20-23, 2022, on line, Oita, Japa

Development and Evaluation of a Tomato Fruit Suction Cutting Device

This paper introduces a structure and harvesting motion for the suction cutting device of a tomato harvesting robot, and reports harvesting experiments conducted in a tomato greenhouse. The suction cutting device comprises a suction part and a cutting part. The suction part separates the target fruit from a tomato cluster and the cutting part cuts the peduncle of the target fruit. A photoresistor in the cutting part assesses whether or not the target fruit is harvestable, and the cutting motion is performed only when the fruit is assessed as harvestable. The harvesting experiments were conducted in a tomato greenhouse to evaluate the suction cutting device. In this experiments, 50 tomato clusters were randomly selected as the harvesting objects, and there were 203 tomato fruits (including immature fruits). Out of the 203 tomato fruits, 114 tomato fruits were mature and within the robot workspace. Out of the 114 tomato fruits, 105 tomato fruits were recognized as target fruits by the harvesting robot. Out of these 105 tomato fruits, 65 tomato fruits were assessed as harvestable and 55 were successfully harvested (the harvesting success rate was 85%). Based on the results of the harvesting experiments, this study clarified the issues of the suction cutting device, classified the fruits according to whether they were easy or difficult to harvest, and evaluated the fruit characteristics qualitatively.2021 IEEE/SICE International Symposium on System Integrations (SII), January 11 - 14, 2021, Iwaki, Fukushima, Japa

Crack Detection in a Concrete Structure Using an Underwater Vehicle

In this paper, to realize efficient underwater infrastructure inspection, automatic crack detection by image processing is proposed. In first process of our method generates enhanced image based on the absorbance from the turbidity meter and removes background component, and then detects crack from the enhanced image by using decision tree learning algorithm. This paper explains the algorithm of our method and shows evaluation experiment 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

Exercise on Environmental Monitoring and Control of Greenhouse by IoT Devices toward Smart Agriculture

As crops in greenhouses are widely distributed, IoT devices placed near the crops should be stand-alone and modular, and data from the devices are collected over the networks. Smart agriculture requires knowledge of a wide range of fields including electricity, information, and image processing. We have designed an AI and IoT technology exercise on environmental monitoring and control of a greenhouse where we have been preparing for grow up of tomatoes and other vegetables.The 2022 International Conference on Artificial Life and Robotics (ICAROB 2022), January 20-23, 2022, on line, Oita, Japa

Sea Trials for Benthos Sampling Using Autonomous Underwater Vehicle

For enhancement of oceanic engineering technology and researchers, underwater robot competition has been held since 2016. Seventh competition in this year consists AUV league that university\u27s vehicles automatically cruise at field and junior league that underwater craft is made. The paper reports competition regulations of AUV and junior league and results of the competition held in October 2019.The 2020 International Conference on Artificial Life and Robotics (ICAROB 2020), January 13-16, 2020, B-Con Plaza, Beppu, Oit

Treatment Strategy for Pancreatic Neuroendocrine Neoplasms (pNEN)

Article信州医学雑誌 68(5): 235-242(2020)journal articl