Naruto University of Education

www.naruto-u.ac.jp/
Naruto, Japan

Naruto University of Education is a national university in Japan. It is located in Naruto, Tokushima. The current president is Yuzo Tanaka. The school employs around 160 professors. Wikipedia.

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News Article | February 15, 2017
Site: www.eurekalert.org

Using the largest set of radiocarbon dates ever obtained from a single Maya site, archaeologists have developed a high-precision chronology that sheds new light on patterns leading up to the two major collapses of the ancient civilization. Archaeologists have long puzzled over what caused what is known as the Classic Maya collapse in the ninth century A.D., when many of the ancient civilization's cities were abandoned. More recent investigations have revealed that the Maya also experienced an earlier collapse in the second century A.D. -- now called the Preclassic collapse -- that is even more poorly understood. University of Arizona archaeologist Takeshi Inomata and his colleagues suggest in a new paper, to be published in the Proceedings of the National Academy of Sciences, that both collapses followed similar trajectories, with multiple waves of social instability, warfare and political crises leading to the rapid fall of many city centers. The findings are based on a highly refined chronology developed by Inomata and his colleagues using an unprecedented 154 radiocarbon dates from the archaeological site of Ceibal in Guatemala, where the team has worked for over a decade. While more general chronologies might suggest that the Maya collapses occurred gradually, this new, more precise chronology indicates more complex patterns of political crises and recoveries leading up to each collapse. "What we found out is that those two cases of collapse (Classic and Preclassic) follow similar patterns," said Inomata, the paper's lead author and a professor in the School of Anthropology in the UA College of Social and Behavioral Sciences. "It's not just a simple collapse, but there are waves of collapse. First, there are smaller waves, tied to warfare and some political instability, then comes the major collapse, in which many centers got abandoned. Then there was some recovery in some places, then another collapse." Using radiocarbon dating and data from ceramics and highly controlled archaeological excavations, the researchers were able to establish the refined chronology of when population sizes and building construction increased and decreased at Ceibal. While the findings may not solve the mystery of why exactly the Maya collapses occurred, they are an important step toward better understanding how they unfolded. "It's really, really interesting that these collapses both look very similar, at very different time periods," said Melissa Burham, one of three UA anthropology graduate students who co-authored the paper. "We now have a good understanding of what the process looked like, that potentially can serve as a template for other people to try to see if they have a similar pattern at their (archaeological) sites in the same area." Inomata and his UA colleagues -- anthropology professor Daniela Triadan and students Burham, Jessica MacLellan and Juan Manuel Palomo -- worked with collaborators at Ibaraki University, Naruto University of Education and the Graduate University for Advanced Studies in Japan, and with Guatemalan archaeologists and students. Radiocarbon dating was done at Paleo Laboratory Company in Japan and at the Accelerator Mass Spectrometry Laboratory in the UA Department of Physics. "Radiocarbon dating has been used for a long time, but now we're getting to an interesting period because it's getting more and more precise," said Inomata, who also is an Agnese Nelms Haury Chair in Environment and Social Justice at the UA. "We're getting to the point where we can get to the interesting social patterns because the chronology is refined enough, and the dating is precise enough." Inomata's research was funded in part by the National Science Foundation, National Endowment for the Humanities, National Geographic Foundation, the Alphawood Foundation and the UA's Agnes Nelms Haury Program in Environment and Social Justice.


Ishida K.,Tokushima University | Hirsch F.,Naruto University of Education
Gondwana Research | Year: 2011

The revision of the Middle and early Late Triassic conodonts in the Nogami (1968) collection from the NW Malaya Kodiang Limestone Formation provides clues to the multi-element reconstruction of Triassic Gondolellacea. Septi- to octomembrate multi-elements characterize the families Gondolellidae and Gladigondolellidae nov. fam. The distribution of cratognathodiform and ozarkodiniform P2 elements supports the hypothesis of sexual dimorphism in Gladigondolella rather than that of two genera. Pseudofurnishius murcianus confers a Southern Tethyan low latitude character to the Kodiang Limestone, a part of the Cimmerian string of terranes that in Triassic times formed a diagonal partition between the gradually closing Paleo-Tethys and the accordingly widening Neo-Tethys. Our findings suggest that such a realm stretched from the Southern Alps (Dinarids) in the West to Malaya (Shan Thai Terrane) in the East. Only the Eastern edge collided with Eurasia in the Late Triassic, forming the platform of Sundaland. Consequently, the Paleo-Tethys closure remained limited to SE Asia, while a substantial Paleo-Tethys still existed in Western direction, ending up in the Pindos and Vardar oceans. The Jurassic Neo-Tethys ocean extended south of the consolidated SE Asia block and Cimmerian string of terranes. © 2010 International Association for Gondwana Research.


Eguchi T.,Kyoto University | Hikami K.,Naruto University of Education
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2011

We discuss the possibility of Mathieu group M24 acting as symmetry group on the K3 elliptic genus as proposed recently by Ooguri, Tachikawa and one of the present authors. One way of testing this proposal is to derive the twisted elliptic genera for all conjugacy classes of M24 so that we can determine the unique decomposition of expansion coefficients of K3 elliptic genus into irreducible representations of M24. In this Letter we obtain all the hitherto unknown twisted elliptic genera and find a strong evidence of Mathieu moonshine. © 2010 Elsevier B.V.


Akimoto T.,Keio University | Miyaguchi T.,Naruto University of Education
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2013

We study a class of random walk, the stored-energy-driven Lévy flight (SEDLF), whose jump length is determined by a stored energy during a trapped state. The SEDLF is a continuous-time random walk with jump lengths being coupled with the trapping times. It is analytically shown that the ensemble-averaged mean-square displacements exhibit subdiffusion as well as superdiffusion, depending on the coupling parameter. We find that time-averaged mean-square displacements increase linearly with time and the diffusion coefficients are intrinsically random, a manifestation of distributional ergodicity. The diffusion coefficient shows aging in subdiffusive regime, whereas it increases with the measurement time in superdiffusive regime. © 2013 American Physical Society.


Akimoto T.,Keio University | Miyaguchi T.,Naruto University of Education
Journal of Statistical Physics | Year: 2014

Phase diagram based on the mean square displacement (MSD) and the distribution of diffusion coefficients of the time-averaged MSD for the stored-energy-driven Lévy flight (SEDLF) is presented. In the SEDLF, a random walker cannot move while storing energy, and it jumps by the stored energy. The SEDLF shows a whole spectrum of anomalous diffusions including subdiffusion and superdiffusion, depending on the coupling parameter between storing time (trapping time) and stored energy. This stochastic process can be investigated analytically with the aid of renewal theory. Here, we consider two different renewal processes, i.e., ordinary renewal process and equilibrium renewal process, when the mean trapping time does not diverge. We analytically show the phase diagram according to the coupling parameter and the power exponent in the trapping-time distribution. In particular, we find that distributional behavior of time-averaged MSD intrinsically appears in superdiffusive as well as normal diffusive regime even when the mean trapping time does not diverge. © 2014, The Author(s).


Miyaguchi T.,Naruto University of Education | Akimoto T.,Keio University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2013

The effects of spatial confinements and smooth cutoffs of the waiting time distribution in continuous-time random walks are studied analytically. We also investigate dependences of ergodic properties on initial ensembles (i.e., distributions of the first waiting time). Here, we consider two ensembles: the equilibrium and a typical nonequilibrium ensemble. For both ensembles, it is shown that the time-averaged mean square displacement (TAMSD) exhibits a crossover from normal to anomalous diffusion due to the spatial confinement and this crossover does not vanish even in the long measurement time limit. Moreover, for the nonequilibrium ensemble, we show that the probability density function of the diffusion constant of TAMSD follows the transient Mittag-Leffler distribution, and that scatter in the TAMSD shows a clear transition from weak ergodicity breaking (an irreproducible regime) to ordinary ergodic behavior (a reproducible regime) as the measurement time increases. This convergence to ordinary ergodicity requires a long measurement time compared to common distributions such as the exponential distribution; in other words, the weak ergodicity breaking persists for a long time. In addition, it is shown that, aside from the TAMSD, a class of observables also exhibits this slow convergence to ergodicity. We also point out that, even though the system with the equilibrium initial ensemble shows no aging, its behavior is quite similar to that for the nonequilibrium ensemble. © 2013 American Physical Society.


Miyaguchi T.,Naruto University of Education | Akimoto T.,Keio University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2015

Models with mixed origins of anomalous subdiffusion have been considered important for understanding transport in biological systems. Here one such mixed model, the quenched-trap model (QTM) on fractal lattices, is investigated. It is shown that both ensemble- and time-averaged mean-square displacements (MSDs) show subdiffusion with different scaling exponents, i.e., this system shows weak ergodicity breaking. Moreover, time-averaged MSD exhibits aging and converges to a random variable following the modified Mittag-Leffler distribution. It is also shown that the QTM on a fractal lattice cannot be reduced to the continuous-time random walks if the spectral dimension of the fractal lattice is less than 2. © 2015 American Physical Society.


Masumoto J.,Hyogo University of Teacher Education | Inui N.,Naruto University of Education
Experimental Brain Research | Year: 2014

The present study examined the development of a leader–follower relationship in joint action performed by participants with different skill levels. Two participants were instructed to produce discrete isometric forces such that the sum of the forces was the target force. The task did not prescribe the onset time or share of force each participant contributed to the target force. Although novices with low force variability did not produce an earlier force than those with high force variability in the novice–novice group, experienced participants produced an earlier force than novices in the novice-experienced group. While participants with low force variability always produced a stronger force than those with high force variability in both the groups, there was no significant difference in force distributions between participants with low and high force variabilities. Although a novice-experienced pair produced force more complementarily than a novice–novice pair in the first practice block, the difference between pairs vanished after the first practice block, suggesting that leader–follower relations were not always beneficial to task performance. In addition, practice of the joint action did not transfer to individual action. © 2014, Springer-Verlag Berlin Heidelberg.


Masumoto J.,Hyogo University of Teacher Education | Inui N.,Naruto University of Education
Experimental Brain Research | Year: 2014

If two people row a boat, they often call to each other to synchronize their strokes. It is anticipated that such a call promotes periodic joint action. The present study thus examined the effects of speech on both complementary and synchronous strategies in joint action using the same task as we used previously (Masumoto and Inui in J Neurophysiol 109:1307-1314, 2013a). Ten pairs of participants produced periodic isometric forces such that the sum of the forces they produced was the target force cycling between 5 and 10 % of maximum voluntary contraction with an interval of 1,000 ms with the right hand. There were three speech conditions crossed with the presence or absence of visual information. Whereas two participants synchronized an utterance/ba/with the peak and valley forces in the 'Both' condition, one synchronized it with both forces in the 'One-side' condition, and nobody uttered it in the 'None' condition. When the total force was visible, the One-side and Both conditions exhibited lower correlations than the None condition, although the correlation between forces produced by two participants was negative in all conditions. When the total force was invisible, although the coherence between force and time series produced by two participants was low under the None condition, it was high at 1 and 3 Hz under the One-side and Both conditions. Thus, although periodically uttering a syllable worsened complementary force production when the target was visible, it promoted synchronization of their performance to each other's timing when the target was invisible. © 2014 Springer-Verlag.


Masumoto J.,Hyogo University of Teacher Education | Inui N.,Naruto University of Education
Journal of Neurophysiology | Year: 2013

If two people lift and carry an object, they not only produce complementary forces on the object but also walk in synchrony. Previous studies have not examined how two types of coordination strategy are adopted simultaneously. The present study thus tested the hypothesis that complementary and synchronous strategies simultaneously facilitate the action coordination performed by two people. Ten pairs of participants produced periodic isometric forces such that the sum of forces they produced was the target force cycling between 5% and 10% of maximum voluntary contraction with an interval of 1,000 ms (joint action), while individuals alone produced the same target forces with the right hand (individual action). The correlation between forces produced by two participants was highly negative when the total force was visible, indicating that the two participants produced complementary forces. When the image of the total or partner force was presented, the coherence between force-time series produced by two participants was highest at 1 Hz. The relative phase angles were also distributed at the 0-20° phase region. These innovative findings indicate that two participants simultaneously adopted both complementary and temporal synchronous strategies exclusively when the total force was visible. With the vision of total force, surprisingly, while the joint action exhibited a less variable force than the individual action, the joint action exhibited a smaller absolute error of forces than the individual action. These new findings indicated that the joint action controlled force more accurately than the individual action. © 2013 the American Physiological Society.

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