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Capturing and Insolubilization of Cesium by Aluminosilicates
Capturing of cesium contained in decontamination waste by aluminosilicate (alkali feldspar)
The insoluble form of cesium in incineration bottom ash was concentrated in the amorphous phase on the surface of a specific mineral, namely, alkali feldspar. This trapping phenomenon is applied to insolubilize cesium in soil and waste generated during decontamination, and we are developing a technology to control the leaching of cesium, even during long-term storage.
Research
The solubility of cesium (Cs) in incineration bottom ash is low due to strong trapping of Cs in the amorphous phase on the surface of microcline, which is a kind of alkali feldspar. When Cs salts such as Cs carbonate and Cs chloride are added to pure microcline and heated, Cs is trapped at an extremely high rate and becomes insoluble (Fig. 1). Since the Cs trapped by this process is fixed very tightly, it cannot be extracted unless hydrofluoric acid is used. Similar Cs trapping occurs when using a reagent to synthesize microcline (Fig. 2). In this study, we are applying this phenomenon of Cs capture by microcline (aluminosilicate) to Cs-enriched materials (e.g., fly ash with high Cs concentration) generated during volume reduction thermal treatment of removed soil and decontamination waste, aiming to establish a technology to reduce the mobility of Cs in the waste to be finally disposed of to the extent possible (Fig. 3).
Yasumasa Tojo Associate Professor -
Use of Lignin, a Wood Component, as an Electronic Device Material
Molding of lignin and its conversion to a functional material
Lignin is second only to cellulose in availability, but the only way to effectively use lignin at present is to burn it for energy production. We are currently working on molding lignin into fibers and films for use as electrodes and separators in electric double-layer capacitors (EDLCs).
Research
EDLCs are electronic devices that are attracting attention as next-generation storage batteries that can replace rechargeable batteries such as Li-ion batteries. The parts called electrodes and separators in EDLCs are made from polymeric materials, so we are conducting research on replacing these polymers with lignin, a major component of woody biomass. By forming lignin into microfibers through electrospinning and converting them into active carbon fibers, we have succeeded in producing the large surface area required for electrode materials. This has led to the production of electrodes with high energy and power densities. In addition, by converting lignin into a flexible polyester film, it became possible to prepare a material that exhibits the same performance as conventional separators. We are currently endeavoring to further improve the performance.
Yasumitsu Uraki Professor -
Spatio-temporal Control of Laguerre-Gaussian Light
Information multiplexing using the spatial phase of light
In this study, we have developed a fundamental technology for information multiplexing using Laguerre-Gaussian (LG) light, which has a characteristic spatial phase. By focusing on the spatial phase, which has not been actively used in conventional optical information processing, we aim to increase the information capacity.
Research
Optical information processing, transmission, recording and reproduction are performed using the intensity, polarization and spatially uniform phase of laser light. The transmission capacity can be increased through multiplexing using different frequencies. In contrast, the spatial characteristics of light form an unexplored area that has not been actively utilized until now. Based on this background, information multiplexing using Laguerre-Gaussian (LG) light and quantum information processing using the orbital angular momentum (topological charge) that characterizes LG light have been attracting attention as a step to overcome the limitation of information processing capacity. In this study, we have utilized material interaction and realized the mode control of LG light and the conversion and conservation of orbital angular momentum using short-pulsed light, as well as space-division multiplexing fiber transmission.
Yasunori Toda Professor -
Simultaneous Observation of Electrical Properties and Structural Changes Using an Electron Microscope
The relationships between electrical properties and structural changes can be evaluated and validated
An electronic device fragment is placed in the electron microscope, and a movable probe electrode is applied to it, enabling observation by the electron microscope while evaluating its electrical characteristics. A MOSFET is connected to the sample side electrode to suppress excessive current. It allows evaluation of the correlation between electrical characteristics and structural changes and is useful to investigate the cause of failures.
Research
Our in-situ electron microscopy system is capable of three-terminal device measurements using two movable probes and a fixed sample holder as electrodes. A MOS transistor is inserted in the sample holder to limit the excess current flow due to stray capacitance.
Microelectronic devices that are almost ready for practical application include devices such as phase-change memory and resistance change memory that can predict structural changes accompanying resistance changes. It is difficult to confirm the mechanism of resistance changes in microdevices due to their high operating speed and nanoscale structure, but this system enables the evaluation of such a mechanism and helps to efficiently investigate the cause of the defective operation and ensure its reliability. By using this system, we can also effectively confirm the operating functions and evaluate the causes of defects in nanostructured functional devices, such as nanomachines and nanostructured secondary batteries, which are expected to be further developed in the future. -
Utilize Archaeological Sites as Cultural and Regional Resources
To Establish a Jomon Ecomuseum in My Community
By surveying archaeological sites and maintaining and preserving them as satellites of an ecomuseum, we are preparing and applying mechanisms to routinely/continuously utilize them as local resources for the people who live there and as cultural resources shared by all humankind.
Research
Instead of treating archaeological sites as an annoyance for development work, we will change their value as local resources for the people living in the area and as cultural resources shared by all human beings. For this purpose, a part of the archaeological sites will be excavated in a planned manner and will be maintained and preserved as a "satellite" of the “ecomuseum.” An ecomuseum is a museum that does not require a roof or walls. Satellites are open-air exhibits. While working with local people to develop and preserve the archaeological sites as historical heritage, we are proud to live in the area and participate in the ecomuseum activities as hosts. The planned excavation of the site will be carried out in cooperation with local people and the board of education as part of the university's “Archaeology Practice” educational program. We find it meaningful to practice part of the university education in the local community, the practice of which then becomes the practice of ecomuseum activities as such.
Yasushi Kosugi Professor -
Development of a Method to Prevent Post-Thoracic Surgery Atrial Fibrillation Using Carnitine
We will conduct a randomized, multicenter study to determine whether perioperative oral carnitine therapy can reduce postoperative atrial fibrillation (POAF) in patients with valvular heart disease. In case of lung and esophageal cancer patients, a single-arm interventional study will be conducted because similar studies have not been conducted before.
Research
Postoperative atrial fibrillation (POAF) after thoracic surgery is a frequent problem leading to increased incidences of stroke, heart failure, and infection, and resulting in prolonged hospitalization. Although beta-blockers are the only effective treatment, their efficacy rate is less than 50%, and their side effects often preclude their use. Recently, carnitine preparations, which are fatty acid metabolism ameliorators, have been reported to suppress arrhythmias after myocardial infarction and coronary artery bypass surgery due to their anti-inflammatory and fatty acid metabolism ameliorating effects. As part of this project, we will conduct a randomized, multicenter study to determine whether perioperative carnitine medication can suppress POAF in patients with valvular heart disease. In case of lung cancer and esophageal cancer patients, a single-arm interventional study will be conducted to evaluate the safety and POAF reduction rate, which will be useful for future randomized studies.
Yasushige Shingu Lecturer -
AR Communication System
Avatar-based augmented reality group communication through sharing of terminal position and posture information
By using avatars as intermediaries, it is possible to communicate beyond the constraints of time and space. In this system, AR communication is realized by sharing the position and posture information of participants in group communication and reflecting it in the behavior of avatars visible from each participant's terminal.
Research
Since conventional avatar-based communication systems are based on one-to-one communication, it is difficult to recognize the position and posture information of each physical person participating in a communication field of three or more people where virtual and real worlds are mixed, and to control the behavior of individual avatars accordingly, while maintaining the integrity of the entire field.
In this research, we have developed an AR communication system that shares the position and posture information of physical people (e.g., smartphone terminals) participating in a communication field through recognition of a common AR target and network linkage between terminals, and reflects this information in the behavior of avatars visible from each terminal. The avatars know who and where the participants are in the communication field, and the avatar changing its pose following the movements on one participant's terminal can be seen by other participants from their own viewpoints.Yoshiaki Takai Professor -
Visual Expression by Computer Graphics
Supporting intellectual and creative activities with computers
We aim to support people’s creative activities using 3D computer graphics. Despite significant development of computer graphics, it is not easy to manipulate 3D information, and we are not yet ready to use this information to support our creative activities. We are exploring a mechanism to freely manipulate information in 3D space and easily create CG images.
Research
To produce images using CG, we have to prepare a huge number of parameters related to shape, camera, lighting, material, etc. To achieve the desired result, these parameters must also be adjusted by trial and error. An extended calculation time is also required to create precise images. This makes it impossible to conduct creative activities using CG. Therefore, we are developing a method to solve these problems. For parameter adjustment, we have introduced the inverse problem approach, and for computation time, we are developing a fast computation method using parallel computation. We are also applying these ideas to digital fabrication using 3D printers. We are also working on the development of a new user interface to reflect the user’s intentions more intuitively.
Yoshinori Dobashi Professor -
System Control Technology Based on Mathematical Methods
From mechanical to energy management systems
System control technology based on mathematical models can be applied to a wide range of fields, from mechanical systems such as four-wheeled robots to social systems such as energy management systems. At this laboratory, we are developing control methods for nonlinear and hybrid systems in particular.
Research
Many systems, such as manipulators and automobile engines, are nonlinear systems. Many conventional methods are created in view of individual cases. In this laboratory, we are developing a unified control method using control Lyapunov functions. As an example, we are considering the development of a four-wheeled robot running on a flat surface (Fig. 1). To achieve obstacle avoidance and movement to the target position, a pseudo height difference is set (Fig. 2). The obstacles are positioned high and the target is positioned low. This allows four-wheeled robots to achieve their control objectives with only one simple rule of following the low position.
Dynamical systems that include switching of dynamics are called hybrid systems, and are known to have many applications. Recently, we have been working on the application of hybrid systems to energy management systems. In particular, we are developing an electricity consumption model for consumers.Yuh Yamashita Professor -
Developing Applications of GIS and Geospatial Information
A human geographical approach to the advanced information society
GIS (Geographical Information System) is a system for analyzing, searching, and displaying geospatial information (data including location information). In this laboratory, we are developing GIS analysis and visualization methods related to geospatial information for the purpose of supporting regional planning and disaster prevention planning.
Research
At this laboratory we are using GIS to study the use of geospatial information, such as Geospatial Information Authority (GSI) maps and digital national land information, maintained by the national government as well as open data maintained by local governments and big data such as movement history acquired by GPS. For example, the results of this research are being used to support the formulation of plans for tsunami evacuation in snowy and cold regions. The winter environment in snowy and cold regions (frozen road surfaces, reduced road width due to snow, etc.) makes tsunami evacuation in coastal areas extremely difficult. At our laboratory we generate a lot of information necessary for planning, such as the demarcation of difficult-to-evacuate areas, the estimation of difficult-to-evacuate populations, and evaluation of the capacity of evacuation sites under such snowy cold conditions, and publish our techniques and results. In this way, we are developing technologies to easily and quickly create socially useful information from a geographical perspective, and are continuing our research to contribute to the formation of the foundation for an advanced information society.
Yuichi Hashimoto Professor -
Catalytic Purification of Nitrate-nitrogen Contaminated Water
High-performance catalyst for reductive decomposition of nitrate-nitrogen
Groundwater pollution with nitrate-nitrogen has become a problem. We have developed a high-performance solid catalyst that promotes decomposition of nitrate-nitrogen in water into nitrogen gas through a reaction with hydrogen gas at room temperature. Using a purification system incorporating this catalyst, we have succeeded in purifying contaminated groundwater.
Research
Groundwater pollution with nitrate-nitrogen has become a nationwide problem. We have developed a high-performance solid catalyst that promotes decomposition of nitrate-nitrogen in groundwater into nitrogen gas, and have also succeeded in purifying actual contaminated groundwater using a purification system incorporating the developed catalyst.
The treatment of water containing nitrate-nitrogen is predominantly a biological treatment that involves anaerobic and aerobic treatment. The equipment for that is generally large and its operation is complicated. The catalytic water purification system we have developed is very compact and does not require complicated operations, making it possible to purify contaminated water simply by passing hydrogen gas and contaminated water through a temperature-controlled reactor filled with catalyst.Yuichi Kamiya Professor -
Creating Appropriate Governance Systems based on Theory and Practice
Making Our Society Safer and More Secure through Public-Private Collaborations
Based on my previous case studies on safety and environmental regulatory processes, science and technology policies, and regional developments, I conduct research on how to create appropriate governance systems that contribute to solving public policy problems in introducing and disseminating advanced technologies into society. Governance theory and practice, through collaboration with stakeholders, will undoubtedly help.
Research
While technology greatly benefits society, it also poses various risks. Therefore, when introducing advanced technology, it is necessary to design governance systems that minimise these risks and to determine the optimal public policies to maximize the benefits.
In the case of automobiles, the perception of the regulatory policy often differs among stakeholders such as manufacturers, regulators, and users. Regulatory policy is also largely determined by harmonized international standards.
As such, I define public policy problems in introducing advanced technology into society based on an understanding of the overall picture, seek a place in which stakeholders can reach an agreement, build consensus, and consider how to create governance systems in which the public and private sectors can cooperate.Yuichi Murakami Associate ProfessorPh.D. -
Development of an Electronic Holographic HMD Device
Ideal 3D image display
We are developing a head-mounted 3D display (HMD) device using electronic holography. This is a compact, lightweight and practical device realized by using a new computational algorithm and a newly designed optical system.
Research
Electronic holography-based display devices can display stress-free 3D images that are compatible with human visual physiology. Using computational correction, the head-mounted display (HMD) developed with this research replaces the complex optical system that had been required in the past, with a simple optical system. As a result, we have achieved the smallest and lightest electronic holography system in the world at low cost. As shown in the figure below, the hologram image can also be displayed to fit in the depth.
Unlike conventional HMDs, this HMD does not cause users stress due to a shift in depth focus.Yuji Sakamoto Professor -
Basic Research to Design Healthy Life Rhythms Considering Biological Clocks
Japanese people sleep less than the global average, and the economic loss due to sleep disorders is estimated to be about 6 trillion yen per year. At our laboratory we specialize in chronobiology, which is the study of the biological clock, which is deeply related to sleep. Our goal is to contribute to the health of the nation by promoting research of chronobiology.
Research
The biological clock is an important biological strategy that regulates our behavior (timing of sleep and wakefulness) and our body’s internal environment, so that we can be fully active during the day and get good sleep at night. However, in today's society, many of us are forced to live against our biological clocks due to night shifts, jet lag, 24-hour work schedules, and so on. In order to lead a healthy life throughout our lives, we need to understand the structure and function of our biological clocks, and actively design and optimize our life rhythms according to our life stages and individual lifestyles. At our laboratory, we are studying the mechanism of the effects of light and exercise on the biological clock, the development of effective nutritional dietary guidance methods based on chrono-nutrition, and the relationship between seasonal variations in sleep and biological rhythms and physiological functions.
Yujiro Yamanaka Associate ProfessorPh.D. in Medicine -
Mitochondria-targeted Nanocapsules (MITO-Porter)
Technology to introduce drugs, proteins and nucleic acids into mitochondria
The mitochondrion is attracting attention as an organelle that contributes to the treatment of diseases, maintenance of beauty and health and the development of the life sciences. We have successfully developed a mitochondria-targeted nanocapsule (MITO-Porter) and are aiming to commercialize this nanocapsule.
Research
The mitochondria-targeted nanocapsules (MITO-Porter) in this study can pass through the cell and mitochondrial membranes to deliver target molecules inside the mitochondria. Conventional technologies using functional elements severely limit the size and type of molecules to be delivered, but the strategy using MITO-Porter, which encapsulates the target molecule, enables mitochondrial delivery independent of the molecular species.
When we prepared MITO-Porter with GFP (green) encapsulated and observed intracellular fluorescence microscopy, we observed many yellow signals that overlap with mitochondria (red), confirming efficient molecular delivery inside the mitochondria. We have also succeeded in introducing genes and nucleic acids into mitochondria, which had been impossible with existing nucleic acid delivery agents (targeting the nucleus and cytoplasm). We are also developing nanocapsules that can be adapted to living organisms.Yuma Yamada Professor -
An Organizational Study of Tourism Associations as DMOs
Focusing on the differences in strategies depending on organizational structures and organizational culture
DMOs (destination management organizations), which are attracting attention as a national policy, are studied, mainly from the perspective of organizational theory.
Research
With the growing interest in the Japanese version of DMO, tourism associations are now expected to play a leading role in the promotion of tourism in the region. However, tourism associations were originally formed for the purpose of resource management, such as conservation associations or trade associations of tourism-related businesses. Therefore, for the tourism association to become a DMO, it has to undergo fundamental changes as an organization. This study examines the nature of such changes from an organizational perspective.
For example, in the field of organization theory, it is said that certainty in consensus building and the means to achieve goals can define the strategy that a leader should adopt, and we believe that these theories can also be applied to tourism associations. By identifying the leaders in a tourism association, their strategies, and how to control the organization based on the organizational structure and culture, we can conduct practical research on how to develop a tourism association into a DMO.Yusuke Ishiguro Associate Professor -
Susceptibility Testing of Molecular-targeted Therapeutic Drugs
Visualization technique of drug responsiveness in individual cells using fluorescence bioimaging
Fluorescence bioimaging is a technique to visualize the cell behavior at the single cell level. Using this method, we have applied the imaging technology to visualize drug responsiveness and resistance, and to predict future drug responsiveness of patients.
Research
This diagnostic technique uses fluorescent proteins and a fluorescent biosensor based on the principle of F?rster resonance energy transfer (FRET).
By visualizing the drug responsiveness at the single cell level with this biosensor, it has become possible to detect a very small number of drug-resistant cells. As a result, we have achieved a high concordance rate with the clinical course after administration and prediction of future drug responsiveness, both of which were not possible with conventional technology. This technology is not only the world’s first clinical application of fluorescent proteins, but also expected to help assure safety by selecting therapies with guaranteed efficacy. This will also bring economic benefits to medicine by reducing the financial burden on patients and the medical costs. We are now proceeding with this project for chronic myeloid leukemia, which is a blood cancer, as a model. In principle, this technology can be applied to various cancers.Yusuke Ohba Professor -
In Vivo Nucleic Acid Delivery System Based on the Development of Unique Functional Lipids
Balancing world-class functional delivery of nucleic acids and safety
We have developed a unique group of functional lipids for the safe and efficient in vivo delivery of siRNA. The lipid nanoparticles containing these lipids showed world-class functional delivery of siRNA in hepatocytes due to their excellent endosomal escape ability and high safety due to their biodegradability.
Research
The key to the practical application of siRNA is the development of superior delivery technology, but there is still much room for improvement in the delivery efficiency. In addition, from the viewpoint of practicality, it is also important to secure a wide safe therapeutic window. It is also highly desirable to develop platform technologies that can provide appropriate formulations for different purposes without being limited to specific applications. To achieve these goals, we have developed a unique group of pH-sensitive cationic lipids. We achieved the modulation of acid dissociation constants, which is an important factor for the pharmacokinetics of lipid nanoparticles, enabling a target-specific molecular design. The lipid nanoparticles containing the novel lipid CL4H6 induced gene silencing in hepatocytes with world-class efficiency. No significant hepatotoxicity was also observed even after the administration of approximately 3,000-fold higher dose for 50% gene silencing, thus a high level of safety was confirmed. CL4H6 was rapidly degraded and eliminated after siRNA delivery.
Yusuke Sato Assistant Professor -
Development of Polymer Electrolyte Fuel Cells with Excellent Sub-zero Start-up Performance
Elucidation of micro-nano freezing phenomena in fuel cells
We are visualizing the freezing phenomenon near the reaction layer in fuel cells, which cannot normally be observed, using an ultracold electron microscope. By combining electrochemical measurements, we are also elucidating the freezing phenomenon of produced water, which becomes a problem in cold climate applications, and are developing fuel cells with excellent sub-zero activation performance.
Research
In the polymer electrolyte fuel cell (PEFC), which is a highly efficient and clean energy conversion device, the water produced by the reaction passes through a catalyst layer pores of several tens of nanometers in diameter and is discharged into the gas diffusion layer and gas supply channel through the microporous layer (MPL), which is a porous layer with pores of several micrometers in diameter, as shown in the left figure below. In the activation in a sub-zero environment in cold regions, the produced water freezes, causing the power generation to stop and degrade. However, the phenomenon is on a micro-nano scale and is thus difficult to measure, so the phenomenon is still insufficiently understood. This study is aimed to clarify where the water freezes and what mechanism leads to performance shutdown and aging degradation. We will conduct microscopic observation, electrochemical measurement and catalyst layer model analysis to contribute to the improvement of activation resistance and extension of the service life. The middle figure below shows the catalyst layer filled with ice, and the right figure is a structural schematic of the catalyst layer modeled in the analysis.
Yutaka Tabe Professor
