OIST-Kyudai Joint Symposium Series 1: Bio-Inspired Wonders and Energy Innovations

Elongated robot arms that can access confined spaces are useful in many applications, such as invasive surgery, search and rescue, and inspection. However, their reach is often limited because their extension mechanism relies on elastic deformation or folding structures. To address this challenge, I propose a robot with a novel extension mechanism inspired by the impressive ability of woodpeckers to extend and bend their long tongues to catch insects in tree holes. The proposed mechanism can change the robot length almost zero to any length by moving the robot's body back and forth.

I have applied powder and particle materials in manufacturing processes. Using nano-powder materials, I am developing fine patterning techniques for ceramics and glass. Additionally, I utilize magnetic particles in the development of composite materials for magnetic field-driven actuators. This technology finds application in soft robots driven by external magnetic fields. Moreover, I have employed this approach in the development of artificial hair. I am also interested in exploring the application of these techniques to biomimicry engineering, incorporating them into studies of biological systems.

1: High speed, high linearity and low noise system LSI components (low noise amplifiers, power amplifiers, mixers, digitally-controlled oscillators etc.) for wireless communication systems.
2: Electrically small antennas and array antennas. 
3: Interconnection and packaging technology of a chip to an antenna to reduce parasitic components.
4: RF Energy harvesting circuit for IoT (internet of things), and medical, health care and agricultural applications.

Terahertz wave is an electromagnetic wave with a frequency between 0.1 and 10 THz, which has properties of transparency as a radio wave as well as directivity and broadband as a lightwave. Applications that make use of these characteristics include ultra-high frequency wireless communications, ultra-high resolution radar, imaging and sensing. We are using photonics technologies, such as photomixing and an optical phased array, to generate terahertz waves and control these phases in the 0.1-3 THz range. In this workshop, the principles of terahertz-wave generation and phase control using optical technology as well as research trends in application fields that utilize its advantageous characteristics will be presented.

Foldable wings of insects are the ultimate deployable structures and have attracted the interest of engineers as well as entomologists. The aim of this study is to leverage the exceptional folding mechanisms in the wings of these insects to develop innovative deployable structures and lightweight constructions. The presentation will explain the crease pattern design method based on the folding mechanism of earwig wings, elucidated through the geometry of origami. Additionally, various deployable structures developed from this approach will be discussed.

Photofunctional materials are materials that exhibit useful functions via a change in optical, electrical, or chemical properties by photoirradiation. To observe the dynamical processes in these materials in-situ and realtime, we have developed time-resolved analytical methods using ultrashort pulse lasers. We have recently studied the CO2 photoreduction processes in artificial photosynthesis using time-resolved infrared vibrational spectroscopy and revealed electron transfer mechanism and identified intermediate species. Also, we have studied the emission processes in organic light emitting diode using time-resolved photoluminescence and transient absorption spectroscopy and revealed structural factor in spin-flip processes and detailed electron transfer processes in host-guest amorphous films.

Fluid machinery (e.g., automobiles, aircraft, engines, and power generators) works with force and energy obtained from fluid flow and usually enriches our life. When designing fluid machinery, it is necessary to consider various design candidates and find one of them that can meet design requirements. Traditionally, it has been carried out based on the designer's knowledge, experience, and intuition, but it gets more complicated as the design problem becomes more extensive and complex. Therefore, our laboratory is working on the data-driven and data-informed design of fluid machinery, independent of a designer's skill and based on fluids engineering integrated with mathematical and data sciences. Through the research mentioned above, our laboratory aims to contribute to designing and manufacturing various engineering machinery, including fluid machinery.

The search for causative mutations in human genetic disorders has mainly focused on mutations that disrupt coding regions or existing splice sites. Recently it has been reported that mutations creating splice sites can also cause a range of genetic disorders. However, such splice-site-creating mutations (SCMs) have only been sporadically reported as being involved in genetic disorders to date. Hence, the overall picture of the extent to which SCMs are involved as a cause of genetic disorders is still unclear. To address this question, we sought to identify SCMs that could be involved in various genetic disorders using SpliceAI and the variant information registered in the public database. We identified 3,942 possible SCMs that are likely to be pathogenic in 4,054 genes responsible for genetic disorders. This finding suggests that SCMs are mutations worth focusing on in the search for causative mutations of genetic disorders.

Single-walled carbon nanotubes (SWCNTs) are promising thermoelectric materials because of their high electrical conductivity and Seebeck coefficient. To construct a thermoelectric generator (TEG) employing SWCNTs, the development of n-type regions within a single piece of p-type SWCNTs (p-n patterning) has gained interest, offering a seamless TEG structure without the need for metal electrodes to bridge the p- and n-type regions. We have demonstrated p-n patterning of SWCNT films by spray, thermal deposition, and UV irradiation methods so far. In this joint-symposium, I will talk about the p-n patterning process of SWCNT films by photoinduced electron doping using photobase generators and the planar-type TEG devices constructed by this technique.

Heavy metals released from mining development and other anthropogenic activities are causing serious contamination of groundwater and other aquatic environments. In contrast to conventional remediation methods that often rely on chemicals and energy inputs, bioremediation and metal-biotechnologies utilizing microbial metabolism present promising alternatives. These approaches offer advantages such as high reaction rates, selectivity in catalytic reactions, and a potential reduction in overall environmental impact. Microorganisms have developed mechanisms to tolerate and catalyze redox transformation of toxic metal(loid)s, such as arsenic. In natural systems, toxic metalloids are often strongly adsorbed to solid minerals such as Fe(III) oxyhydroxides, and microbe-mineral interactions play crucial roles in both iron and metal(loid) transformations. This presentation aims to explore the Heavy metals released from mining development and other anthropogenic activities are causing serious contamination of groundwater and other aquatic environments. In contrast to conventional remediation methods that often rely on chemicals and energy inputs, bioremediation and metal-biotechnologies utilizing microbial metabolism present promising alternatives. These approaches offer advantages such as high reaction rates, selectivity in catalytic reactions, and a potential reduction in overall environmental impact. Microorganisms have developed mechanisms to tolerate and catalyze redox transformation of toxic metal(loid)s, such as arsenic. In natural systems, toxic metalloids are often strongly adsorbed to solid minerals such as Fe(III) oxyhydroxides, and microbe-mineral interactions play crucial roles in both iron and metal(loid) transformations. This presentation aims to explore the diversity of microbial pathways involved in metal(loid) transformations and discuss their potential in bioremediation and other biotechnological application. 

The purpose of our research is to elucidate local structural changes of materials at the nanoscale by using state-of-the-art transmission electron microscopy. By controlling the various environments such as the irradiation electron beam, observation atmosphere, and temperature, we will realize ideal advanced measurements that reflect the original structure and phenomena of materials, which cannot be achieved by conventional electron microscopic observation. 

Our group investigates such functional materials synthesized by the anionic four-coordinate/penta-coordinate molecules with cyanides combined with various metal ions or organic cations. In particular, we found that the penta-coordinate mixed-anion units [MN(CN)4]2- (M = Mn, Cr, Re) produce several ‘self-clustering’ forms such as tetranuclear cluster, cyanide-bridged chains and nitrido-bridged chains in A2X type hybrids (A = organic cations). The A2X type hybrids consist of more dynamic structural characteristics than the conventional perovskite-type hybrids, thus, they exhibit various phase transition behavior and chemical responsivity. For example, (PyC3)2[ReN(CN)4] shows a water induced large transformation where re-arrangements of [ReN(CN)4]2- units occur between chain-type assembly and tetranuclear cluster form. This transformation gives rise to a switching of luminescent properties between visible (560 nm) and near-infrared (740 nm) emissions.

The Amakusa Marine Biological Laboratory (AMBL), originally established as a centre of research in marine biology in temperate–subtropical Japan, has now expanded its sphere of research interests to include a wide area of ecological and biodiversity studies.  AMBL is surrounded by various types of coastal habitats and is located at the boundary of temperate and tropical waters.  These characteristics of the location make the laboratory an ideal place to examine the influence of environmental changes on natural communities.  I devote myself to elucidating how a multitude of species can coexist and maintain ecological assemblages under different environmental conditions and evolutionary backgrounds. 

Climate change caused by emissions of greenhouse gases into the atmosphere is a most important issue for our society. CO2 capture by permselective membranes is advantageous because of its smaller and simpler design. Unfortunately, its efficiency is not satisfactory for practical operation of the DAC. We developed defect-free, free-standing polymeric nanomembranes with a thickness of 34 nm exhibited world-high CO2 permeance. The separation is achieved even at the atmospheric CO2 concentration (ca. 400 ppm). 
Based on these achievements, we first proposed the concept of membrane-based DAC, which was previously considered impossible.3 Our current efforts focus on developing a continuous process from DAC to the production of methane and carbon monoxide, through collaborative research activities.

In nature, biological olfactory systems (e.g. olfactory receptors) are highly sophisticated, and can discriminate various odor molecules with similar structural isomers in a wide concentration range. However, such biological olfactory systems have faced their limitations for artificial olfactory sensor electronics, because of their inherent vulnerability. Thus, it has been a long-standing scientific issue in material chemistry to design robust but molecular selective odor sensing and artificial olfactory systems using robust materials . In this talk, I will present some recent progress of my research group on robust odor sensing and artificial olfactory devices by designing metal oxide nanostructures and their interfaces.  I will also discuss that weak van der Waals interactions between hydrophobic aliphatic alkyl-chains and hydrophilic metal oxide nanostructured surfaces, which have been highly underestimated as interactions during molecular sensing, play an important role on electrical sensing on metal oxide sensor surfaces.

Halide perovskites can be used for many optoelectronic devices with excellent performance. In Kyushu University, we demonstrated durable perovskite solar cells by understanding their degradation mechanisms. By choosing a suitable organic cation, we were able to increase external quantum efficiency of perovskite LEDs from ~3% to ~12%. We fabricated perovskite field-effect transistors exhibiting high hole mobilities of > 10 cm2 V−1 s−1. We first demonstrated continuous-wave lasing from optically pumped perovskite films at room temperature in air. We observed efficient electroluminescence from LEDs, in which an organic emitter is dispersed into a perovskite host layer. We successfully reduced driving voltages or increased a total device thickness of organic LEDs by introducing high-mobility perovskite transport layers.

Nanostructures of graphene are called nanographenes and demonstrate a wide range of optical, electronic, and magnetic properties depending on their size and chemical structures, which renders them promising as next-generation carbon-based nanomaterials. However, it is challenging to accurately control the chemical structures while “cutting” graphene. To this end, large polycyclic aromatic hydrocarbons (PAHs) possess nanoscale graphene structures, attracting a renewed attention as atomically precise nanographenes. We have developed unique nanographenes with high stability and strong emission, showing potential for photonic and bioimaging applications.

pi-Conjugated polymers are being used in the fabrication of a wide variety of organic electronic devices such as organic field-effect transistors (OFETs), organic photovoltaic (OPV) devices, and organic light-emitting diodes (OLEDs). Since the seminal work on the conductivity of polyacetylene by Heeger, MacDiarmid, and Shirakawa was published in 1970s, the field of organic electronics has grown exponentially. Our group has been studying and developing techniques to grow semiconducting polymers using a living polymerization method. This has allowed us to synthesize polymer architectures that we haven’t been able to access till now including polythiophene brushes, star-shaped P3HT, as well as hyperbranched P3HT. It also allows us to accurately control the molecular weights of P3HT and produce materials with a narrow molecular weight distribution. Our unique synthetic capabilities allows us to specifically control defects in these polymers. Our work in controlling polymer defects and their effect on microstructure and thus optoelectronic properties will be presented. More recently, we have been focusing on developing more environmentally benign methods to synthesize the semiconducting polymers.

Mitotic duration is tightly constrained, with extended mitosis being characteristic of problematic cells prone to chromosome missegregation and genomic instability. We show that mitotic extension leads to the formation of p53-binding protein 1 (53BP1)–Ubiquitin-specific protease 28 (USP28)–p53 protein complexes that are transmitted to and stably retained by daughter cells. Complexes assemble through a Polo-like kinase 1 (PLK1) activity-dependent mechanism during prolonged mitosis and elicit a p53 response in G1 that prevents proliferation of the progeny of cells that experienced an 3-fold extended mitosis or successive less extended mitoses. The ability to monitor mitotic extension is lost in p53-mutant cancers and in some p53-wildtype cancers, consistent with classification of 53BP1 and USP28 as tumor suppressors. Cancers that retain the ability to monitor mitotic extension exhibited sensitivity to anti-mitotic agents.

Determining the origins and adaptive utility of novel traits is at the core of evolutionary biology; how such traits influence the diversification of groups is at the core of macroevolution (evolution at the species level and above). Understanding the origins and spread of traits can require information from multiple areas of organismal biology (e.g. development, biomechanics, phylogenetics) at multiple scales. The 35,000 living species of fishes provide essential data on all these aspects, enhanced by an abundant fish fossil record that preserves many relevant features. Here, I show how an interdisciplinary approach to fish biodiversity helps tease apart the origins and diversification of novel traits. This approach has helped answer ongoing questions about “key innovations,” function of novel features, and the ecological circumstances in which new traits arise.

As more renewable sources are added to meet our energy requirements, grid integration and stability has become an immediate, real and important problem to address for utilities and grid operators. Understanding the character of fluctuations among various renewable energy sources and how they interact with each other at the grid level is therefore of great import. In this talk, I will provide a brief overview of our efforts in this area.

Coming soon...

Charge carriers are important in photoelectric conversion and emission devices such as solar cells and light-emitting diodes. In organic materials, charge generation is more difficult than inorganic materials, and photoinduced charge separation using an electron-donor-acceptor interface is usually used. However, the generated charge is quickly deactivated by recombination in the organic semiconductors.
By stabilizing the charge-separated states, we have realized unique luminescence phenomena such as persistent luminescence and stimulated luminescence, which have been difficult to achieve with organic materials.

Our life develops from fertilized eggs according to a program engraved in the genome. Genomic information is transcribed into mRNA that dictates production of proteins. Information from the environment affects production and degradation of mRNA. Data are accumulating that the CCR4-NOT complex governs mRNA fate and is thus important in gene regulation. To investigate the biological significance of this complex in detail, we generated mouse lines deficient of each of the subunit proteins, CNOT1-3, CNOT6/6L, CNOT7/8, and CNOT9-11, and found that the complex plays important roles in regulation of survival, proliferation, and differentiation of the cell. For example, Cnot9 KO mice do not develop beyond embryonic day 9.5. I will discuss here possible mechanism of gene regulation mediated by the CNOT9 protein.

I have been in an inspiring loop from X-ray crystallography to electron microscopy and EUV lithography, all of which are wave physics that I have enjoyed in my life.
1980 (Kyushu University) "Light generation by relativistic electron and EM wave".
1990 (Stanford University) "Laser interference and nanometer electron collision": I invented it in Italy (one year sabbatical), then we proved it at SLAC Stanford in 1995.
2000 (RIKEN) "EUV source and SACLA X-ray laser for crystallography". Technical leader on this big project, cost 350 M$ and 10 years time.
2011~ (OIST) "Diffraction physics" of electron in electron microscope and EUV lithography.
They are all in the same physics inspired by Bragg diffraction phenomena.

The primary focus of my research is to deepen understanding of emergent phenomena driven by many electrons in low-dimensional quantum materials and their interfaces. Target functionality includes, for example, ferroelectricity, magnetism, metal-insulator transition, and superconductivity. It is widely recognized that the development of emergent phenomena at the nano-scale holds immense significance for advancing future nano-electronics, nano-spintronics, nano-optics, and the broader field of hybrid quantum device applications, surpassing conventional silicon technology. To support this endeavor, I have recently established an advanced and state-of-the-art laboratory facility that synergistically combines synthesis and spectroscopic techniques, empowering our team to search various unexplored areas of quantum materials and their heterointerfaces. In my talk, I will introduce some of our recent findings in exotic 2D material in which excitonic band deformation happens together with emergent weak ferromagnetism.

Polymer, Photochemistry

luminescence, polymer, emission

Bioinspired Photonic Materials

Liquid Crystalline Cellulosic Polymers, Light-Driven Structural Colors, Cellulose Nanocrystals, Photochromic Molecular Switch

artificial life, complexity science

pattern formation, self-assembly, self-organization

molecular bilogy

translation, misfolding, ribosome

Biophysics, Statistical Physics

Spiderweb, statistical walk, trapping, predator-prey interaction

Marine Biology

Kuroshio current, spawning, gonadosomatic index, maturity, sex ratio

C-H Activation, organic synthesis

C-H Arylation, room temperature, benzofuran

Marine Ecology

species distribution modelling, mobulid rays, Aotearoa New Zealand, boosted regression tree, conservation biology

Organometallic chemistry

Organometallic, Metallocene, Ferrocene, 18-electron rule

Protein engineering; Synthetic biology

RNA methylation; Ancestral sequence reconstruction

Biosensors

Surface Imprinted Polymers; Escherichia coli; Ready2use Materials; 3D printing

Nonlinear and non equilibrium physic

Renewable fluctuations, Consumer load fluctuations, Dynamic load balancing

Physics

Turbulence, Extreme events, Stochastic processes, Fluid mechanics, Wind turbines

Nonlinear physics / Soft matter / Granular material

Impact-induced hardening / suspension / colloid