I reconstruct paleovegetation by pollen analysis contained in sediments such as lakes and marshes, and elucidate how the environment changed in the past. I also research the human impacts on vegetation using charcoal analysis. Currently, I am focusing on the chronological study of human migration to the eastern Polynesia. In addition, we measure airborne pollen, understand the scattering status of hay fever pollen. And we report these data to the Japan Meteorological Association, and forecast scattering for the next year.

We investigate various biological characteristics such as genetics, morphology, physiological reproduction, and nutrition of wild animals, especially small mammals, through breeding and preservation of their breeding stock (e.g., suncus and voles). To elucidate the diverse biosystems in humans and other animals, we aim to create unique animal resources that enable us to obtain knowledge that is difficult to obtain with common laboratory animals (e.g., mice and rats) and to improve their added value.

Hepatocyte growth factor (HGF) was originally identified as an hepatotrophic factor. During the past 30 years, we provided evidence to show that HGF plays an essential role for regeneration of several types of organs, including kidney, lung, hearts and neural tisses, using animal models of intractable disorders. HGF elicits unique biological activities, such as mitogen, motogen and morphgen via activating c-Met/HGF-receptor tyrosine kinase as shown below. Of note, a loss in HGF production is responsible for manifestation of acute and chronic organdiseases. This is the reason why HGF supplemental therapy produces benefit effects against the progression of acute and chronic organ diseases.

Primates (precisely non-human primates), are the animal group that shares the most similarities with humans. They show high levels of intelligence and social skills. Additionally, many primate species live in tropical and subtropical regions and are considered keystone species that play a fundamental role in maintaining tropical ecosystems. Researching the society and ecology of primates can provide us with valuable insights into the evolution and nature of humans. This knowledge can help us better understand ourselves, as well as contribute to the conservation of biodiversity and the resolution of global environmental issues. My work involves studying the society and ecology of primates and other large and medium-sized mammals, mainly through field observations. I also examine human society from a zoological perspective and its evolution. Currently, my team and I are conducting long-term field research and conservation activities to protect wild gorillas in the tropical forests of Central Africa. We also conduct educational and animal welbeing activities in zoos and perform behavior observation research on Japanese macaques in Japan.

We focus on the ecology of wild animals, including endangerd species, and their function in the ecosystem using direct observation or research tools such as camera trap. We explore better conservation methods and way for a sustainable coexistence with people.

Mammanlian reproductive status changes during postnatal development and aging. It can also be altered by environmental cues, stress or dysfunction of related organs. My research aims to clarify the factors and the mechanism which affect reproductive functions by using histological analysis on hypothalamic-pituitary-gonadal axis and measuring reproductive hormones. I am also working to establish methods to monitor reproductive status of wild animals by measuring steroid hormones in hair.

Various industrial products are made of solid materials such as metals, polymers, and ceramics. Although all solid materials deform elastically and plastically when forces are applied, their deformation behavior strongly depends on deformation mechanisms. Therefore, it is indispensable to understand their deformation properties to produce useful machines and durable apparatuses. Our laboratory has been working on subjects that aim to apply solid materials for various engineering applications; clarification and evaluation of deformation properties of engineering materials, study on influences of microstructure upon deformation properties of solids, and development of new forming techniques.

Examination of production conditions for soft magnetic amorphous ribbons by liquid rapidsolidification method using precipitation hardening Cu alloy rolls. In this paper, we investigated that production conditions for amorphous ribbons by liquid rapid solidification method.

Studies on Control Strategy for Multi-body Systems
We can take each of the machines as a system that is composed of many parts including adjacent parts that are connected by a joint so that they can move relative to each other. We can typically assume that each part is rigid enough that it will never bend or twist while in motion. Such a part is called a rigid body. We can consider industrial robotic arms and even automobiles as systems with rigid bodies. When the rigid bodies in the system move, various forces are applied to the system from the inside. Then, we must ask, what is the relationship between the forces and the motions of the rigid bodies? In the control engineering laboratory, we study such problems for mechanical systems and try to control or measure the mechanical values of the system in order to obtain effective control methods.
Studies on Dynamic Mass Measurement
We also try to obtain effective estimation methods for some mechanical values of the system (including total mass) based on dynamics. Solving the problem of measuring the weights of heavy in-motion vehicles with high precision belongs to the field of dynamic mass measurement.

Bone histology is the study of internal bone tissues, and provides important clues to physiological and ecological aspects of extinct animals such as the growth rate, longevities, potential metabolism and aquatic adaptation.
I am currently conducting researches on bone histology of large tetrapods (e.g., dinosaur, mammal and amphibians) to understand their gigantism, dwarfism and aquatic adaptations.

Ashworth scales have been used as a method to evaluate the muscle tonus of the patient having spasticity.This method however cannot evaluate it without the enforcer’s subjective judgment.Therefore we analyze the motion of leg by measuring pendulum motion (Pendulum Test) to evaluate the spasticity objectively.

The picture shows two one axis accelerometer were attached to a leg to measure leg motion.Because the angle output of the leg is only provided by the motion capture directly, 2 times differential calculus operation is necessary to obtain the angular acceleration output convenient to evaluate.In contrast, the angular acceleration output is provided directly with our method.

High temperature superconducting (HTS) wires have good characteristics such as perfect electric conductivity and large critical current density. Therefore the HTS wires are expected to contribute to development of small, lightweight and very efficient electric power apparatus. I am currently conducting researches on development of a small power source with an HTS transformer for supplying large current, a protection system for normal transitions in superconducting coils and a superconducting rotating gantry for heavy ion therapy.

In recent years, almost all digital systems have operated in synchronization with the clock pulse. However, high-frequency clock pulses not only increase the power consumption but also cause instability in the system. In our laboratory, we are working on the applications of an asynchronous circuit without clock pulses, for example, improving the performance of large-scale digital systems and reducing the power consumption of biometric signal processors. The proposed architectures are designed and implemented in the reconfigurable programmable gate array (FPGA), and we are also working on the FPGA-based image processing accelerator for surveillance camera systems and medical diagnostic imaging systems.

I do research the image processing using color effects and visual characteristics. For example, the human visual features vary with on age. I advance the development of a lightness transform method considering the visual features of the elderly person.

IT technologies are advancing at breakneck speed, driven in particular by advances in AI and IoT. While connecting vast amounts of information to the internet has enhanced convenience, it has also increased the risk of personal data and corporate confidential information being compromised. This laboratory focuses on securing IoT devices—which typically have limited computational resources and pose significant security challenges—and develops and implements security measures. We primarily concentrate on cryptography and random number generation, exploring applications of these technologies in IoT devices including FPGAs, as well as encryption for various communication channels and device authentication. Furthermore, we are committed to the real-world deployment of IoT technology.

The interactions of surfactants with proteins have been widely studied. Recently, an attention has been paid to the effects of surfactants on the secondary structural changes of proteins denatured by another denaturing factor.

Aiming to achieve both comfort and energy efficiency, which are essential for future architecture, we are conducting research to realize safe and healthy living spaces. Specifically, we are working to improve the efficiency of “air-based floor heating and cooling systems,” which excel at heating and cooling large spaces. We are also advancing research on environmental control utilizing natural energy and energy-saving renovations of existing buildings. Furthermore, we are working to improve the temperature and humidity environment of homes and reduce the air conditioning load through the development of “functional building materials” with moisture absorption and release and heat storage properties. Through these practical approaches using the optimal combination of air conditioning equipment and building materials, we are promoting research aimed at creating sustainable and high-quality buildings and living environments.

More than ten thousands people died caused fatal accidents in houses every year in Japan. Among them a number of the aged people died in falling down to flat floor even though without any steps. Floor slipperiness is usually represented as static friction coefficient at the slips in toe-off during last half of gait cycle. However, it is said that slips are also occurred at heel down to floor during first half of gait cycle. In order to evaluate floor slipperiness at heel down, it is necessary to measure the dynamic friction coefficient between footwear and floor under incremental vertical load during the heel down.
The wear of UHMWPE(ultrahigh molecular weight polyethylene) used in artificial joint is investigated more than 5 million cycles using joint simulator. The simulator is reproduced vertical load, flexion/extension, abduction/adduction and internal/external rotaion during gate cycle.

By taking advantage of pneumatic actuators that have features of higher force / mass ratio, lightweight and flexibility based on compressibility, we have developed low-cost wearable actuators and low-cost home-based rehabilitation devices that can be disposable after using it. Specifically, we developed a flexible pneumatic cylinder that can be used even if the cylinder bends. A spherical actuator that consists of two flexible pneumatic cylinders have been also developed as an application for portable rehabilitation device. We have also developed a low-cost wearable servo valve using buckled tubes, an artificial muscle with built-in displacement sensor and a pipe inspection robot using extension type flexible pneumatic actuators. In addition, aiming at globalization for students, all graduate students in our laboratory have presentation in international conferences.

The theme of our laboratory is to measure biological information obtained from humans and animals. Measured biological information is used in the development of various sensors, equipment, and software.