Research Report 1
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RESEARCH REPORT 1. Name: Justin Acheson （ID No.: SP13001） 2. Current affiliation: University of Wisconsin Madison 3. Research fields and specialties: Biological Sciences 4. Host institution: University of Tokyo 5. Host researcher: Hideaki NOJIRI 6. Description of your current research Electron-transfer plays an essential role in the cellular processes of all living organisms, and in most cases must be achieved by transient protein-protein interactions. In order to achieve efficient transfer, while deterring spurious and possibly detrimental interactions, organisms have evolved interacting partners to share complimentary surfaces as well as redox affinity. Multi-component enzymes systems like non-heme iron oxygenases are a ubiquitous and evolutionarily related group of enzymes capable of carrying out catalysis on a diverse group of compounds, and rely on these interactions. To perform their reactions, exogenous electrons must be derived through the aforementioned controlled protein-protein interactions. My current research at the University of Wisconsin – Madison has focused on diiron monoxygenase systems, which insert a single oxygen from the relatively inert molecular oxygen into unactiaved C-H bonds. These chemically intensive reactions are under rigorous investigation to unlock the key to their catalytic cycles, opening new avenues for inexpensive production of feed chemicals in industry, and better options for bioremediation. 7. Research implementation and results under the program Title of your research plan: Effects of redox state in protein-protein electron-transfer complexes Description of the research activities: Research in the Nojiri Lab is diverse, but follows a central theme, aimed at understanding the microbiology and biochemistry of toxic compound degrading organisms. During my stay I was able to learn new techniques that complement my own research, including isothermal titration calorimetry (ITC). This powerful technique allows researchers to understand binding characteristics in proteins where ligands are either small molecules, or another macromolecule including protein and DNA binding partners. In the case of multi-component enzyme systems where multiple binding interactions must occur for efficient catalysis, it is important to understand how the partners interact. Unfortunately due to protein limitations, and unforeseen set backs, I was unable to perform all the experiments I had hoped. However, I learned some important interaction characteristics that are both intriguing and challenging. I hope to continue the further experiments that should be performed with a collaboration with the Nojiri Lab. 8. Please add your comments, including any cultural experience during your stay in Japan (if any): Lab life in Japan is a little different than what I am used to at home, but at the end of the day everyone has the same goals. My host lab is much larger than my thesis lab, and all of the students were extremely welcoming and all seemed to take an active interest in each other’s research. Lab meetings were incredibly long, but were always followed by a nice party. While in Japan I was fortunate to make connections with many Japanese people, as well as foreign researchers engaged in long-term stay. This allowed me to take part in many aspects of Japanese culture that would have been much more difficult due to language deficiency and being an outsider by myself. Being in Tokyo, this helped me see more of the city, eat better food, and learn the city itself, although I did spend a good deal of time exploring on my own. My first real cultural immersion to the past of Japan was multiple trips to Kamakura for hiking and visiting temples. From there on it was a slew of events, climbing Fuji, going to clubs/concerts, museums, travelling to Fukuoka to eat the best foods, more temples, towers and cities. I am glad I purchased a JR rail pass. I hope to come back as a short term post doc, the Summer Program is amazing, but I feel I need to spend longer here. RESEARCH REPORT 1. Name: Jesse P Angle （ID No.: SP13002） 2. Current affiliation: University of California, Irvine 3. Research fields and specialties: Engineering Sciences 4. Host institution: Institute of Engineering Innovation, The University of Tokyo 5. Host researcher: Prof. Yuichi IKUHARA 6. Description of your current research This project focuses on determining the deformation mechanism in a widely used ceramic material, mullite (3Al2O3•2SiO2). Even with its uses in the aerospace and electronics industries, many of the essential mechanical properties of this material still remain unknown and by understanding the fundamental deformation mechanism of slip, both the slip direction and slip direction (or slip-system), a complete characterization of the mechanical properties of mullite can be achieved. In order to correctly determine the slip-system in mullite, dislocations, or a misalignment in the crystal lattice, must be generated, observed and measured. While previous experiments have attempted to determine the slip-system in mullite, it is believed they were unable to create the necessary localized stress needed for dislocation generation. A novel in-situ Transmission Electron Microscopy (TEM) nano indentation technique been successfully used by Prof. Ikuhara’s research group to study dislocation interaction at the grain boundary interface of SrTiO3. This technique will be used to form indentations on the edge of a polycrystalline mullite specimen to create a plastic deformation region and create dislocations. One advantage of this technique is that dislocation can be observed while they are being generated. These dislocations, imaged as black lines that intersect the top and bottom of the TEM foil, will tell if the proposed planes are the slip planes in addition to verifying the slip directions. Previous research has shown the slip directions for mullite are the possibly the [100], [010] and [001] directions in the orthorhombic crystal system. We postulate that the slip planes for mullite will be the atomically dense (100) and (010) planes, but not (001) as strongly bonded chains of polyhedra along the c-axis make (001) slip unlikely. As such, the expected slip systems are [001](100), [010](100), [100](010) and [001](010). Determination of the slip planes will allow the future design of anisotropic microstructures that limit deformation at high temperatures. A result of this project will be to design, manufacture and use critical engineering compounds made of mullite with a much high degree of reliability, and will see direct impact in the aerospace sector where mullite is currently used in high temperature fiber reinforced composites. 7. Research implementation and results under the program Title of your research plan: In-situ Transmission Electron Microscopy Indentation to Characterize Deformation in Ceramics Description of the research activities: Two components were required to obtain results. The first being specimen preparation and the second TEM indentation. Each specimen was required to be a specific geometer and thickness (≈200 nm), before indentation. Once specimen preparation was complete, the specimen was loaded into the in-situ indenter apparatus and a region was selected for indentation. The figure to the right shows the tip of the indenter and a grain of mullite before indentation. The diffraction pattern in the top right of the figure was used to determine the orientation of the grain. Knowledge of specimen orientation is required to determine the slip plane if a dislocation observed. Unfortunately, the in-situ indentation of polycrystalline mullite did not result in the formation of dislocation since each grain tested fractured before dislocation generation occurred. Without dislocation formation the slip-system could not be determined. From these experiments, it was concluded that the stress required for dislocation generated at room temperature is larger than the stress required for fracture and such, in-situ TEM indentation may not be an appropriate technique for determining the slip-system in mullite. 8. Please add your comments, including any cultural experience during your stay in Japan (if any): During my stay in Japan I was invited on two professional visits. The first was to Prof. Teruyasu Mizoguchi lab at the Institute of Industrial Science and second was to Prof. Yoshikazu Suzuki lab at the University of Tsukuba. These visits gave me a great opportunity to speak with students, visit the campus and learn more about the graduate studies system in Japan. In addition to my professional visits, I took time traveled to many of the culturally significant cities and regions in Japan. Including Tokyo (where I was staying), Tsukuba, Narita, Osaka, Kyoto, Nara and Kobe. There I visited shrines, temples, parks, museums and famous landmarks; along with sampling some of the local delicacies. RESEARCH REPORT 1. Name: Kimberly Suzanne Bowen （ID No.: SP13003 ） 2. Current affiliation: University of Utah Department of Psychology 3. Research fields and specialties: Social Sciences 4. Host institution: Kyoto University Kokoro Research Center 5. Host researcher: Dr. Yukiko Uchida 6. Description of your current research Humans are social animals, and social support is a universal aspect of relationships. Social support is also reliably associated with mental and physical health outcomes. However, social support can result in either benefits or costs to health, depending on contextual factors. As a graduate student at the University of Utah, my research