Sanda, Japan

Kwansei Gakuin University , colloquially abbreviated to Kangaku , is a non-denominational Christian private and coeducational university located in Nishinomiya, Sanda, Osaka City, and Tokyo, Japan. Chartered in 1932, it is the 13th institution with university status in Kansai region, the 23rd-oldest outside of Greater Tokyo, and the 46th-oldest in the country. Kwansei Gakuin University is one of oldest and leading private universities in Japan. It has relatively strong network of alumni in Kansai region and has produced a number of CEOs in Japanese companies and politicians. Wikipedia.

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News Article | October 6, 2016

Iron-based superconductors can conduct electricity without resistance at unusually high temperatures relative to those of conventional superconductors, which must be chilled to near absolute zero (minus 459 degrees Fahrenheit) to release their superconducting powers. In addition, they're relatively easy to bend and can carry electrical current easily in different directions under high magnetic fields before superconductivity becomes suppressed. These characteristics make iron-based superconductors promising for advanced energy applications, from electric vehicles to wind turbines and medical imaging devices. However, the amount of current they can carry has been low in comparison to other superconductors. Scientists have been trying to increase this amount, but doing so has often come at the cost of degrading another key superconducting property--the critical temperature at which superconductivity emerges. Now, a team of scientists has come up with a way to double the amount of electrical current an iron-based material can carry without losing its superconducting properties, while increasing the material's critical temperature. Their method, reported in a paper published today in Nature Communications, makes use of a readily available technology that could be used to improve the performance of superconducting wires and tapes. "By bombarding the material with protons at low energy, we simultaneously increased the material's current-carrying capacity and critical temperature--the first time that this has been possible in an iron-based superconductor," said physicist Qiang Li, head of the Advanced Energy Materials Group at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory, who directed the research. "There are low-energy ion facilities all over the world that can do this inexpensively." Shooting ions at superconducting materials is a well-established method for artificially introducing defects in the crystal structure or chemistry of the materials to increase the amount of current they can carry. These defects "pin" in place, or trap, the microscopic magnetic vortices that form when the superconductor is placed in a strong magnetic field, such as those generated by magnets in magnetic resonance imaging (MRI) machines. If free to move around, the vortices dissipate energy, thereby destroying the superconductor's ability to carry electrical current without energy loss. Unfortunately, if the defects produced by ion irradiation create too much disorder in the superconductor, they lower its critical temperature. Because superconductors currently require extreme cooling to conduct electricity without resistance, any decrease in the critical temperature is undesirable. In a Goldilocks sense, the defects must be "just right"--not too big, not too small. Scientists can design such defects by selecting the appropriate ion species (e.g., protons, gold ions, argon ions) and ion energy. "Some ions or energies may cause large enough damage to interfere with superconductivity, while others may not produce any effect at all," explained coauthor Toshinori Ozaki, a former scientist in Brookhaven Lab's Advanced Energy Materials Group who is now a faculty member at Japan's Kwansei Gakuin University. "So we run simulations to figure out what combination should produce the optimal defect--one that can hold down the magnetic vortices without negatively impacting the material's superconducting properties." In the case of the iron-based material the team studied, low-energy protons did the trick. Using electron microscopes, the scientists took images of the thin films (about 100 nanometers thick) of the material they prepared, before and after they hit the films with low-energy protons. "Throughout the irradiated films, we saw individual chains of defects created by the collisions between the incident ions and nucleus that broke the perfect atomic order, causing the lattice to locally compress or stretch out," said coauthor Lijun Wu, a materials scientist at Brookhaven who led the microscopy work. In a performance check, the scientists measured the amount of electrical current running through the films in low and high magnetic fields. In high fields, the irradiated films carried more current than any low-temperature superconductor. This result suggests that the defects and local lattice strain must be strongly pinning the magnetic vortices that would otherwise impede the flow of current. To figure out what caused the surprising increase in the critical temperature, the team created a strain "map" that laid out where the locally compressed and tensile (stretched out) regions were located. Previous studies had already shown that the type of lattice strain correlates with the critical temperature: highly compressed regions with a high critical temperature, and highly tensile regions with a low critical temperature. In the team's films, the compressive ones took up much more space, leading to an overall raised critical temperature. According to Li, these performance gains are only the beginning: "We believe that the critical current and temperature can be further enhanced by fine tuning the structure of the defects and the arrangement of the lattice strains."

Igata T.,Kwansei Gakuin University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

The existence of stable bound orbits of test particles is one of the most characteristic properties in black hole spacetimes. In higher-dimensional black holes, due to the dependence of gravity on the spacetime dimensions, there is no stable bound orbit balanced by Newtonian gravitational monopole force and centrifugal force, although this balance occurs in the four-dimensional Kerr black hole. In this paper, however, the existence of stable bound orbits of massive and massless particles is shown in six-dimensional singly spinning Myers-Perry black holes with a value of the spin parameter larger than a critical value. The innermost stable bound orbits and the outermost stable bound orbits are found on the rotational axis. © 2015 American Physical Society.

Imaoka S.,Kwansei Gakuin University
International Review of Cell and Molecular Biology | Year: 2011

Protein disulfide isomerase (PDI) is a folding assistant in the endoplasmic reticulum (ER) of eukaryotic cells. PDI has multiple roles, acting as a chaperone, a binding partner of other proteins, and a hormone reservoir as well as a disulfide isomerase in the formation of disulfide bonds. PDI only interacts covalently with the cysteines of its substrates, but also binds a variety of peptides/proteins and small chemical ligands such as thyroid hormone. Oxidative stress and nitrosative stress can cause damage to chaperones, protein misfolding, and neurodegenerative disease, by affecting the functional integrity of PDI. There are 20 putative PDI-family members in the ER of human cells, but their functional differentiation is far from complete. This review discusses recent advances in our understanding of the mammalian PDI family of enzymes and focuses on their functional properties and interaction with substrates and small chemical ligands. © 2011 Elsevier Inc.

The article seeks to explicate a link between energy and long-term economic growth and development. While in many ways intuitive, attempts at sketching theoretical frameworks explicating this link have been few and simplistic, typically limited to technology and economics. This article emphasizes the importance of politics as well, fostering a symbiosis between the dominant industries of a historical epoch and the energy system that enabled them to flourish. The framework combines Joseph Schumpeter and Mancur Olson, emphasizing 1) the importance of structural economic change for long-term growth and development and 2) vested interests. The framework yields one theoretical proposition: In order to rise, states must prevent vested interests from blocking structural change. States that are unable to do this will get locked into yesterday's technologies, industries and energy systems, effectively consigning themselves to stagnation and decline. A brief empirical section provides historical data from 6 historical epochs (including present-day renewables) over a period of 250 years to demonstrate the usefulness of the approach. While no exhaustive test, the data suggests that countries that have prevented vested interests from blocking change have been far more successful in fostering a symbiosis between energy and industry than those countries that have not. © 2009 Elsevier Ltd. All rights reserved.

Tanabe I.,Kwansei Gakuin University | Ozaki Y.,Kwansei Gakuin University
Chemical Communications | Year: 2014

Absorption spectra (150-300 nm) of TiO2 and TiO2 modified with metal (Pt, Pd, and Au) nanoparticles were systematically measured using an attenuated total reflection-far ultraviolet spectrometer. The deposition of metal nanoparticles altered the spectral shape and intensity, indicating changes in the electronic states and photocatalytic activities of TiO2. This journal is © The Royal Society of Chemistry.

Ozaki Y.,Kwansei Gakuin University
Analytical Sciences | Year: 2012

The purpose of this review article is to outline recent progress in near-infrared (NIR) spectroscopy. Some particular emphasis is put on the delineation of its versatility in analytical chemistry. NIR spectroscopy is versatile in many aspects. For example, it is electronic spectroscopy as well as vibrational spectroscopy. It is also all-round in applications from basic to practical applications. NIR spectroscopy can be applied to various kinds of materials, bulk materials, thin or thick polymers, tablets, human bodies, and so on. It is particularly powerful in non-invasive, non-destructive, and in situ analysis. In this review, the principles and advantages of NIR spectroscopy are described first, and then its applications to various fields, including polymer science, on-line monitoring, inorganic material research, medical diagnosis, and NIR imaging are introduced. © The Japan Society for Analytical Chemistry.

Tanaka K.,Kwansei Gakuin University
Bioscience, Biotechnology and Biochemistry | Year: 2010

There is mounting evidence that replication defects are the major source of spontaneous genomic instability in cells, and that S-phase checkpoints are the principal defense against such instability. The S-phase checkpoint mediator protein Mrc1/Claspin mediates the checkpoint response to replication stress by facilitating phosphorylation of effector kinase by a sensor kinase. In this review, the multiple functions and the regulation of the S-phase checkpoint mediator are discussed.

Ino H.,Kwansei Gakuin University
Journal of Environmental Economics and Management | Year: 2011

We investigate a model that considers disposal and recycling activities after the consumption of products. In the field, the deposit-refund (D-R) policy has been considered as an ideal policy for internalizing disposal costs, which can result in the realization of the first-best policy. However, the possibility of firms' illegal disposal has been neglected. We introduce a monitoring cost to prevent firms from disposing of collected residuals illegally and induce the second-best D-R policy. We find that the relation between the monitoring problem for firms and the price of the recycling market brings about a variation in the optimal level of the refunds (which is typically smaller than the first-best level). Further, we investigate an alternative policy that requires producers to take-back residuals and show how this policy works equivalently to the second-best D-R policy by applying the theory of the tradable rights market. © 2011 Elsevier Inc.

Nishiyama R.,Kwansei Gakuin University
Psychonomic Bulletin and Review | Year: 2014

In research on verbal working memory, articulatory rehearsal, a maintenance mechanism for phonological representations, has undergone intensive and excellent study. Possible mechanisms for semantic representation have received less attention. However, several studies have reported a double dissociation in types of memory deficits (semantic memory difficulties vs. phonological memory difficulties). This suggests the separability of two maintenance mechanisms. The present study focused on this separability in individuals with normal memory abilities, using a dual-task interference paradigm. The results indicate a crossover interaction between memory and interference task effects: Preventing articulatory rehearsal more strongly disrupted the phonological memory task, whereas performing a tapping task that interfered with attentional control more strongly disrupted semantic memory. These results suggest that semantic representations are actively maintained by a mechanism other than phonological maintenance. © Psychonomic Society, Inc. 2014.

Nakajima Munekage Y.,Kwansei Gakuin University
Current Opinion in Plant Biology | Year: 2016

The structure of thylakoids in chloroplasts and the organization of the electron transport chain changed dynamically during the evolution of C4 photosynthesis, especially in the nicotinamide adenine dinucleotide phosphate (NADP)-malic enzyme type C4 species. Stacked grana membranes are strongly reduced in the bundle sheath chloroplasts of these plants, where photosystem II activity is diminished and cyclic electron transport around photosystem I mainly occurs. This change optimizes the ATP/NADPH production ratio in bundle sheath chloroplasts to drive the metabolic cycle of C4 photosynthesis. This review summarizes the current model of light harvesting and electron transport in the NADP-malic enzyme type C4 plants and discusses how it changed during the evolution of C4 photosynthesis. © 2016 Elsevier Ltd.

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