14,830 results on '"A. Fukaya"'
Search Results
2. Four-Axis Adaptive Fingers Hand for Object Insertion: FAAF Hand
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Fukaya, Naoki, Yamane, Koki, Masuda, Shimpei, Ummadisingu, Avinash, Maeda, Shin-ichi, and Takahashi, Kuniyuki
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Computer Science - Robotics - Abstract
Robots operating in the real world face significant but unavoidable issues in object localization that must be dealt with. A typical approach to address this is the addition of compliance mechanisms to hardware to absorb and compensate for some of these errors. However, for fine-grained manipulation tasks, the location and choice of appropriate compliance mechanisms are critical for success. For objects to be inserted in a target site on a flat surface, the object must first be successfully aligned with the opening of the slot, as well as correctly oriented along its central axis, before it can be inserted. We developed the Four-Axis Adaptive Finger Hand (FAAF hand) that is equipped with fingers that can passively adapt in four axes (x, y, z, yaw) enabling it to perform insertion tasks including lid fitting in the presence of significant localization errors. Furthermore, this adaptivity allows the use of simple control methods without requiring contact sensors or other devices. Our results confirm the ability of the FAAF hand on challenging insertion tasks of square and triangle-shaped pegs (or prisms) and placing of container lids in the presence of position errors in all directions and rotational error along the object's central axis, using a simple control scheme., Comment: 8 pages. Accepted at IEEE IROS 2024. An accompanying video is available at https://www.youtube.com/watch?v=s3yf2MQ5Pag
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- 2024
3. The index of lattice Dirac operators and $K$-theory
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Aoki, Shoto, Fukaya, Hidenori, Furuta, Mikio, Matsuo, Shinichiroh, Onogi, Tetsuya, and Yamaguchi, Satoshi
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Mathematics - K-Theory and Homology ,Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Lattice ,High Energy Physics - Theory ,Mathematics - Differential Geometry - Abstract
We mathematically show an equality between the index of a Dirac operator on a flat continuum torus and the $\eta$ invariant of the Wilson Dirac operator with a negative mass when the lattice spacing is sufficiently small. Unlike the standard approach, our formulation using $K$-theory does not require the Ginsparg-Wilson relation or the modified chiral symmetry on the lattice. We prove that a one-parameter family of continuum massive Dirac operators and the corresponding Wilson Dirac operators belong to the same equivalence class of the $K^1$ group at a finite lattice spacing. Their indices, which are evaluated by the spectral flow or equivalently by the $\eta$ invariant at finite masses, are proved to be equal., Comment: 51 pages, 3 figures
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- 2024
4. Internal 1000 AU-scale Structures of the R CrA Cluster-forming Cloud -- I: Filamentary Structures
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Tachihara, Kengo, Fukaya, Naofumi, Tokuda, Kazuki, Yamasaki, Yasumasa, Nishioka, Takeru, Abe, Daisei, Inoue, Tsuyoshi, Harada, Naoto, Shoshi, Ayumu, Nozaki, Shingo, Sato, Asako, Omura, Mitsuki, Fujishiro, Kakeru, Fukagawa, Misato, Machida, Masahiro N., Kanai, Takahiro, Oasa, Yumiko, Onishi, Toshikazu, Saigo, Kazuya, and Fukui, Yasuo
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Astrophysics - Astrophysics of Galaxies - Abstract
We report on ALMA ACA observations of a high-density region of the Corona Australis cloud forming a young star cluster, and the results of resolving internal structures. In addition to embedded Class 0/I protostars in continuum, a number of complex dense filamentary structures are detected in the C18O and SO lines by the 7m array. These are sub-structures of the molecular clump that are detected by the TP array as the extended emission. We identify 101 and 37 filamentary structures with a few thousand AU widths in C18O and SO, respectively, called as feathers. The typical column density of the feathers in C18O is about 10^{22} cm^{-2}, and the volume density and line mass are ~ 10^5 cm^{-3}, and a few times M_{sun} pc^{-1}, respectively. This line mass is significantly smaller than the critical line mass expected for cold and dense gas. These structures have complex velocity fields, indicating a turbulent internal property. The number of feathers associated with Class 0/I protostars is only ~ 10, indicating that most of them do not form stars but rather being transient structures. The formation of feathers can be interpreted as a result of colliding gas flow as the morphology well reproduced by MHD simulations, supported by the the presence of HI shells in the vicinity. The colliding gas flows may accumulate gas and form filaments and feathers, and trigger the active star formation of the R CrA cluster., Comment: 24 pages, 13 figures; Accepted for publication in ApJ
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- 2024
5. SAID-NeRF: Segmentation-AIDed NeRF for Depth Completion of Transparent Objects
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Ummadisingu, Avinash, Choi, Jongkeum, Yamane, Koki, Masuda, Shimpei, Fukaya, Naoki, and Takahashi, Kuniyuki
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Computer Science - Robotics ,Computer Science - Computer Vision and Pattern Recognition - Abstract
Acquiring accurate depth information of transparent objects using off-the-shelf RGB-D cameras is a well-known challenge in Computer Vision and Robotics. Depth estimation/completion methods are typically employed and trained on datasets with quality depth labels acquired from either simulation, additional sensors or specialized data collection setups and known 3d models. However, acquiring reliable depth information for datasets at scale is not straightforward, limiting training scalability and generalization. Neural Radiance Fields (NeRFs) are learning-free approaches and have demonstrated wide success in novel view synthesis and shape recovery. However, heuristics and controlled environments (lights, backgrounds, etc) are often required to accurately capture specular surfaces. In this paper, we propose using Visual Foundation Models (VFMs) for segmentation in a zero-shot, label-free way to guide the NeRF reconstruction process for these objects via the simultaneous reconstruction of semantic fields and extensions to increase robustness. Our proposed method Segmentation-AIDed NeRF (SAID-NeRF) shows significant performance on depth completion datasets for transparent objects and robotic grasping., Comment: 8 pages. An accompanying video is available at https://www.youtube.com/watch?v=S4NCoUq4bmE
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- 2024
6. Design of supercurrent diode by vortex phase texture
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Fukaya, Yuri, Mercaldo, Maria Teresa, Margineda, Daniel, Crippa, Alessandro, Strambini, Elia, Giazotto, Francesco, Ortix, Carmine, and Cuoco, Mario
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Condensed Matter - Superconductivity - Abstract
We investigate supercurrent nonreciprocal effects in a superconducting weak-link hosting distinct types of vortices. We demonstrate how the winding number of the vortex, its spatial configuration and the shape of the superconducting lead can steer the sign and amplitude of the supercurrent rectification. We find a general criterion for the vortex pattern to maximize the rectification amplitude of the supercurrent. The underlying strategy is the search of specific vortex core position yielding a vanishing amplitude of the supercurrent first harmonic. We also prove that supercurrent nonreciprocal effects can be used to diagnose high-winding vortex and to distinguish between different types of vorticity. Our results thus provide a toolkit to control the supercurrent rectification by means of vortex phase textures and nonreciprocal signatures to detect vortex states with nonstandard phase patterns., Comment: 7 pages and 3 figures + 9 pages and 6 figures
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- 2024
7. Discovery of Asymmetric Spike-like Structures of the 10 au Disk around the Very Low-luminosity Protostar Embedded in the Taurus Dense Core MC 27/L1521F with ALMA
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Tokuda, Kazuki, Harada, Naoto, Omura, Mitsuki, Matsumoto, Tomoaki, Onishi, Toshikazu, Saigo, Kazuya, Shoshi, Ayumu, Nozaki, Shingo, Tachihara, Kengo, Fukaya, Naofumi, Fukui, Yasuo, Inutsuka, Shu-ichiro, and Machida, Masahiro N.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
Recent Atacama Large Millimeter/submillimeter Array (ALMA) observations have revealed an increasing number of compact protostellar disks with radii of less than a few tens of astronomical units and that young Class 0/I objects have an intrinsic size diversity. To deepen our understanding of the origin of such tiny disks, we performed the highest-resolution configuration observations with ALMA at a beam size of $\sim$0$''$03 (4 au) on the very low-luminosity Class 0 protostar embedded in the Taurus dense core MC 27/L1521F. The 1.3 mm continuum measurement successfully resolved a tiny, faint ($\sim$1 mJy) disk with a major axis length of $\sim$10 au, one of the smallest examples in the ALMA protostellar studies. In addition, we detected spike-like components in the northeastern direction at the disk edge. Gravitational instability or other fragmentation mechanisms cannot explain the structures, given the central stellar mass of $\sim$0.2 $M_{\odot}$ and the disk mass of $\gtrsim$10$^{-4}$ $M_{\odot}$. Instead, we propose that these small spike structures were formed by a recent dynamic magnetic flux transport event due to interchange instability that would be favorable to occur if the parental core has a strong magnetic field. The presence of complex arc-like structures on a larger ($\sim$2000 au) scale in the same direction as the spike structures suggests that the event was not single. Such episodic, dynamical events may play an important role in maintaining the compact nature of the protostellar disk in the complex gas envelope during the main accretion phase., Comment: 13 pages, 5 figures, Accepted for publication in ApJ
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- 2024
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8. Corrigendum of 'Construction of Kuranishi structures on the moduli spaces of pseudo holomorphic disks I, Surveys in Differential Geometry XXII (2018), 133-190'
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Fukaya, Kenji, Oh, Yong-Geun, Ohta, Hiroshi, and Ono, Kaoru
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Mathematics - Symplectic Geometry ,53D40, 53D12, 53D37 - Abstract
This is a corrigendum of Lemma 9.1 of the paper [FOOO3] in the title. This lemma is not correct as pointed out by A. Daemi and a referee of the paper [DF]. The corrigendum does not affect the applications of this lemma in [FOOO3] and other papers and exactly the same proofs as therein apply if one replaces the statement of [FOOO3,Lemma 9.1] by Lemma 2 of the present note., Comment: 7 pages
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- 2024
9. Blown-up corona of relatively hyperbolic groups
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Fukaya, Tomohiro
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Mathematics - Group Theory ,Mathematics - Geometric Topology ,20F65 - Abstract
We show that under appropriate assumptions, a blown-up corona of a relatively hyperbolic group is equivariant and the compactification of the universal space for proper action by the blown-up corona is contractible. As a corollary, we establish the formula to determine the covering dimension of the blown-up corona by the cohomological dimension of the group. We also show that the blown-up corona of a hyperbolic group with respect to an almost malnormal family of quasiconvex subgroups is homeomorphic to the Gromov boundary of the group., Comment: 32 pages
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- 2024
10. A lattice formulation of Weyl fermions on a single curved surface
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Aoki, Shoto, Fukaya, Hidenori, and Kan, Naoto
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High Energy Physics - Lattice ,Condensed Matter - Mesoscale and Nanoscale Physics ,High Energy Physics - Theory - Abstract
In the standard lattice domain-wall fermion formulation, one needs two flat domain-walls where both of the left- and right-handed massless modes appear. In this work we investigate a single domain-wall system with a nontrivial curved background. Specifically we consider a massive fermion on a $3D$ square lattice, whose domain-wall is a $2D$ sphere. In the free theory, we find that a single Weyl fermion is localized at the wall and it feels gravity through the induced spin connection. With a topologically nontrivial $U(1)$ link gauge field, however, we find a zero mode with the opposite chirality localized at the center where the gauge field is singular. In the latter case, the low-energy effective theory is not chiral but vectorlike. We discuss how to circumvent this obstacle in formulating lattice chiral gauge theory in the single domain-wall fermion system., Comment: 26 pages, 12 figures, minor corrections, published version
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- 2024
11. Boundary of free products of metric spaces
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Fukaya, Tomohiro and Matsuka, Takumi
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Mathematics - Metric Geometry ,Mathematics - Algebraic Topology ,Primary 51F30, Secondary 20F65, 58B34 - Abstract
In this paper, we compute (co)homologies of ideal boundaries of free products of geodesic coarsely convex spaces in terms of those of each of the components. The (co)homology theories we consider are, $K$-theory, Alexander-Spanier cohomology, $K$-homology, and Steenrod homology. These computations led to the computation of $K$-theory of the Roe algebra of free products of geodesic coarsely convex spaces via the coarse Baum-Connes conjecture., Comment: 32 pages, 3 figures
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- 2024
12. Visualizing the spatial distribution of ustalic acid in the fruiting body of Tricholoma kakishimeji
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Ito, Tetsuro, Taira, Syu, Aoki, Wataru, Nagai, Hiroyuki, Fukaya, Masashi, Ryu, Kaori, and Yamada, Akiyoshi
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- 2024
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13. Axial U(1) symmetry near the pseudocritical temperature in $N_f=2+1$ lattice QCD with chiral fermions
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Aoki, Sinya, Aoki, Yasumichi, Fukaya, Hidenori, Hashimoto, Shoji, Kanamori, Issaku, Kaneko, Takashi, Nakamura, Yoshifumi, Rohrhofer, Christian, Suzuki, Kei, and Ward, David
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High Energy Physics - Lattice ,High Energy Physics - Phenomenology - Abstract
We study the $U(1)_A$ anomaly at high temperatures of $N_f=2+1$ lattice QCD with chiral fermions. Gauge ensembles are generated with M\"obius domain-wall (MDW) fermions, and the measurements are reweighted to those with overlap fermions. We report on the results for the Dirac spectra, the $U(1)_A$ susceptibility, and the topological susceptibility in the temperature range of $T=136$, $153$, $175$, and $204$ MeV, where the up and down quark masses are set to be near the physical point as well as at lighter or heavier masses., Comment: 10 pages, 4 figures, 1 table; Proceedings of the 40th International Symposium on Lattice Field Theory (Lattice 2023), July 31st - August 4th, 2023, Fermilab, Batavia, Illinois, USA
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- 2024
14. Study of Chiral Symmetry and $U(1)_A$ using Spatial Correlators for $N_f=2+1$ QCD at finite temperature with Domain Wall Fermions
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Ward, David, Aoki, Sinya, Aoki, Yasumichi, Fukaya, Hidenori, Hashimoto, Shoji, Kanamori, Issaku, Kaneko, Takashi, Goswami, Jishnu, and Zhang, Yu
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High Energy Physics - Lattice - Abstract
Based on simulations of 2+1 flavor lattice QCD with M\"obius domain wall fermions at high temperatures, we compute a series of spatial correlation functions to study the screening masses in mesonic states. We compare these masses with the symmetry relations for various quark masses and lattice sizes at temperatures above the critical point. Using these spatial correlation functions we examine the $SU(2)_L \times SU(2)_R$ symmetry as well as the anomalously broken axial $U(1)_A$ symmetry. Additionally we explore a possible and emergent chiral-spin symmetry $SU(2)_{CS}$., Comment: 10 pages, 5 figures, Contribution to the 40th International Symposium on Lattice Field Theory (Lattice 2023)
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- 2024
15. Chiral susceptibility and axial U(1) anomaly near the (pseudo-)critical temperature
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Aoki, S., Aoki, Y., Fukaya, H., Hashimoto, S., Kanamori, I., Kaneko, T., Nakamura, Y., Suzuki, K., and Ward, D.
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High Energy Physics - Lattice - Abstract
We investigate relations between the chiral susceptibility and axial $U(1)$ anomaly in lattice QCD at high temperatures. Employing the exactly chiral symmetric Dirac operator, we separate the purely axial $U(1)$ breaking effect in the connected and disconnected chiral susceptibilites in a theoretically clean manner. Preliminary results for two-flavor lattice QCD near the critical temperature are presented., Comment: 9 pages, 3 figures, LATTICE2023, minor corrections
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- 2024
16. A Microscopic study of Magnetic monopoles in Topological Insulators
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Aoki, Shoto, Fukaya, Hidenori, Kan, Naoto, Koshino, Mikito, and Matsuki, Yoshiyuki
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High Energy Physics - Lattice ,Condensed Matter - Mesoscale and Nanoscale Physics ,High Energy Physics - Theory - Abstract
In this article, we analyze a magnetic monopole in topological insulators. The monopole obtain a fractional electric charge because of the Witten effect. We consider this system with a microscopic view by adding the Wilson term to the ordinary Dirac Hamiltonian. The Wilson term yields the positive mass shift to the effective mass of the electrons, then the curved domain-wall is dynamically generated around the monopole. The zero-modes of the electrons are localized on the domain-wall, which can be identified as the source of the electric charge., Comment: 9 pages, contribution to the 40th International Symposium on Lattice Field Theory (Lattice2023), July 31st - August 4th, 2023, Fermi National Accelerator Laboratory
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- 2024
17. A lattice regularization of Weyl fermions in a gravitational background
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Aoki, Shoto, Fukaya, Hidenori, and Kan, Naoto
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High Energy Physics - Lattice ,Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Theory - Abstract
We report on a lattice fermion formulation with a curved domain-wall mass term to nonperturbatively describe fermions in a gravitational background. In our previous work in 2022, we showed under the time-reversal symmetry that the edge-localized massless Dirac fermion appears on one and two-dimensional spherical domain-walls and the spin connection is induced on the lattice in a consistent way with continuum theory. In this work, we extend our study to the Shamir type curved domain-wall fermions without the time-reversal symmetry. We find in the free fermion case that a single Weyl fermion appears on the edge, and feels gravity through the induced spin connection. With a topologically nontrivial $U(1)$ gauge potential, however, we find an oppositely chiral zero mode at the center where the gauge field is singular., Comment: 9 pages, 6 figures. Talk presented at the 40th International Symposium on Lattice Field Theory (Lattice2023), 31 July - 4 August 2023, Fermi National Accelerator Laboratory, minor corrections
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- 2024
18. Back-action supercurrent diodes
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Margineda, Daniel, Crippa, Alessandro, Strambini, Elia, Fukaya, Yuri, Mercaldo, Maria Teresa, Ortix, Carmine, Cuoco, Mario, and Giazotto, Francesco
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Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Superconductivity - Abstract
Back-action refers to a response that retro-acts on a system to tailor its properties with respect to an external stimulus. This self-induced effect generally belongs to both the natural and technological realm, ranging from neural networks to optics and electronic circuitry. In electronics, back-action mechanisms are at the heart of many classes of devices such as amplifiers, oscillators, and sensors. Here, we demonstrate that back-action can be successfully exploited to achieve $\textit{non-reciprocal}$ transport in superconducting circuits. Our device realizes a supercurrent diode, since the dissipationless current flows in one direction whereas dissipative transport occurs in the opposite direction. Supercurrent diodes presented so far rely on magnetic elements or vortices to mediate charge transport or external magnetic fields to break time-reversal symmetry. In our implementation, back-action solely turns a conventional reciprocal superconducting weak link with no asymmetry between the current bias directions into a diode, where the critical current amplitude depends on the bias sign. The self-interaction of the supercurrent with the device stems from the gate tunability of the critical current, which uniquely promotes up to $\sim$88% of magnetic field-free signal rectification and diode functionality with selectable polarity. The concept we introduce is very general and can be applied directly to a large variety of devices, thereby opening novel functionalities in superconducting electronics.
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- 2023
19. Intelligent Generation of Graphical Game Assets: A Conceptual Framework and Systematic Review of the State of the Art
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Fukaya, Kaisei, Daylamani-Zad, Damon, and Agius, Harry
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Computer Science - Graphics ,Computer Science - Artificial Intelligence - Abstract
Procedural content generation (PCG) can be applied to a wide variety of tasks in games, from narratives, levels and sounds, to trees and weapons. A large amount of game content is comprised of graphical assets, such as clouds, buildings or vegetation, that do not require gameplay function considerations. There is also a breadth of literature examining the procedural generation of such elements for purposes outside of games. The body of research, focused on specific methods for generating specific assets, provides a narrow view of the available possibilities. Hence, it is difficult to have a clear picture of all approaches and possibilities, with no guide for interested parties to discover possible methods and approaches for their needs, and no facility to guide them through each technique or approach to map out the process of using them. Therefore, a systematic literature review has been conducted, yielding 200 accepted papers. This paper explores state-of-the-art approaches to graphical asset generation, examining research from a wide range of applications, inside and outside of games. Informed by the literature, a conceptual framework has been derived to address the aforementioned gaps.
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- 2023
20. Stretching intervention can prevent muscle injuries: a systematic review and meta-analysis
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Takeuchi, Kosuke, Nakamura, Masatoshi, Fukaya, Taizan, Nakao, Gakuto, and Mizuno, Takamasa
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- 2024
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21. Lagrangians, SO(3)-Instantons and Mixed Equation
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Daemi, Aliakbar, Fukaya, Kenji, and Lipyanskiy, Maksim
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- 2024
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22. Precise Well-plate Placing Utilizing Contact During Sliding with Tactile-based Pose Estimation for Laboratory Automation
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Pai, Sameer, Takahashi, Kuniyuki, Masuda, Shimpei, Fukaya, Naoki, Yamane, Koki, and Ummadisingu, Avinash
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Computer Science - Robotics - Abstract
Micro well-plates are an apparatus commonly used in chemical and biological experiments that are a few centimeters thick and contain wells or divets. In this paper, we aim to solve the task of placing the well-plate onto a well-plate holder (referred to as holder). This task is challenging due to the holder's raised grooves being a few millimeters in height, with a clearance of less than 1 mm between the well-plate and holder, thus requiring precise control during placing. Our placing task has the following challenges: 1) The holder's detected pose is uncertain; 2) the required accuracy is at the millimeter to sub-millimeter level due to the raised groove's shallow height and small clearance; 3) the holder is not fixed to a desk and is susceptible to movement from external forces. To address these challenges, we developed methods including a) using tactile sensors for accurate pose estimation of the grasped well-plate to handle issue (1); b) sliding the well-plate onto the target holder while maintaining contact with the holder's groove and estimating its orientation for accurate alignment. This allows for high precision control (addressing issue (2)) and prevents displacement of the holder during placement (addressing issue (3)). We demonstrate a high success rate for the well-plate placing task, even under noisy observation of the holder's pose., Comment: 8 pages, 8 figures, an accompanying video is available at the following link: https://www.youtube.com/watch?v=noyxIYfVxq0
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- 2023
23. An ALMA-resolved view of 7000 au Protostellar Gas Ring around the Class I source CrA-IRS 2 as a possible sign of magnetic flux advection
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Tokuda, Kazuki, Fukaya, Naofumi, Tachihara, Kengo, Omura, Mitsuki, Harada, Naoto, Nozaki, Shingo, Shoshi, Ayumu, and Machida, Masahiro N.
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Astrophysics - Astrophysics of Galaxies - Abstract
Transferring a significant fraction of the magnetic flux from a dense cloud core is essential in the star formation process. A ring-like structure produced by magnetic flux loss has been predicted theoretically, but no observational identification has been presented. We have performed ALMA observations of the Class I protostar IRS 2 in the Corona Australis star-forming region and resolved a distinctive gas ring in the C$^{18}$O ($J$ = 2-1) line emission. The center of this gas ring is $\sim$5,000 au away from the protostar, with a diameter of $\sim$7,000 au. The radial velocity of the gas is $\lesssim1$ km s$^{-1}$ blueshifted from that of the protostar, with a possible expanding feature judged from the velocity-field (moment 1) map and position-velocity diagram. These features are either observationally new or have been discovered but not discussed in depth because they are difficult to explain by well-studied protostellar phenomena such as molecular outflows and accretion streamers. A plausible interpretation is a magnetic wall created by the advection of magnetic flux which is theoretically expected in the Class 0/I phase during star formation as a removal mechanism of magnetic flux. Similar structures reported in the other young stellar sources could likely be candidates formed by the same mechanism, encouraging us to revisit the issue of magnetic flux transport in the early stages of star formation from an observational perspective., Comment: 9 pages, 3 figures, Accepted for publication in the Astronomical Journal Letters
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- 2023
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24. Two-fingered Hand with Gear-type Synchronization Mechanism with Magnet for Improved Small and Offset Objects Grasping: F2 Hand
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Fukaya, Naoki, Ummadisingu, Avinash, Takahashi, Kuniyuki, Maeda, Guilherme, and Maeda, Shin-ichi
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Computer Science - Robotics - Abstract
A problem that plagues robotic grasping is the misalignment of the object and gripper due to difficulties in precise localization, actuation, etc. Under-actuated robotic hands with compliant mechanisms are used to adapt and compensate for these inaccuracies. However, these mechanisms come at the cost of controllability and coordination. For instance, adaptive functions that let the fingers of a two-fingered gripper adapt independently may affect the coordination necessary for grasping small objects. In this work, we develop a two-fingered robotic hand capable of grasping objects that are offset from the gripper's center, while still having the requisite coordination for grasping small objects via a novel gear-type synchronization mechanism with a magnet. This gear synchronization mechanism allows the adaptive finger's tips to be aligned enabling it to grasp objects as small as toothpicks and washers. The magnetic component allows this coordination to automatically turn off when needed, allowing for the grasping of objects that are offset/misaligned from the gripper. This equips the hand with the capability of grasping light, fragile objects (strawberries, creampuffs, etc) to heavy frying pan lids, all while maintaining their position and posture which is vital in numerous applications that require precise positioning or careful manipulation., Comment: 8 pages. Accepted at IEEE IROS 2023. An accompanying video is available at https://www.youtube.com/watch?v=RAO7Qb2ZGNs
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- 2023
25. Homological algebra and moduli spaces in topological field theories
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Fukaya, Kenji
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Mathematics - Symplectic Geometry ,Mathematics - Geometric Topology ,53D37 57R56 57R58 57K31 - Abstract
This is a survey of various types of Floer theories (both in symplectic geometry and gauge theory) and relations among them., Comment: 56 pages 12 Figures
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- 2023
26. Identification of a Male-Produced Aggregation Sex Pheromone in Rosalia batesi, an Endemic Japanese Longhorn Beetle.
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Fukaya, Midori, Kiriyama, Satoshi, Yagami, Saki, Iwata, Ryûtarô, Yasui, Hiroe, Tokoro, Masahiko, Zou, Yunfan, and Millar, Jocelyn
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Cerambycidae ,Rosaliini ,alkylated pyrone ,longhorned beetle ,male-produced aggregation-sex pheromone - Abstract
The longhorned beetle Rosalia batesi Harold (Coleoptera; Cerambycidae) is endemic to Japan, where its range extends from Hokkaido to Kyushu. The colorful adults are well-known to entomologists and collectors worldwide. It is a hardwood-boring species with larvae that develop in dead broad-leaf trees. In laboratory bioassays, females were attracted to males, which suggested that males produce a sex pheromone. The congeneric species R. alpina is native to Europe, and another congener, R. funebris, is distributed in North America. The pheromone components produced by males of these species had been previously identified as two compounds from different biosynthetic pathways. In the present study, volatiles were collected from beetles of both sexes, and the analyses of the resulting extracts revealed a single male-specific compound, which was identified as 3,5-dimethyl-6-(1-methylbutyl)-pyran-2-one; this is the same compound as the pheromone of the European R. alpina. This alkylated pyrone structure is, so far, unique among known cerambycid pheromones. In field bioassays with traps baited with the racemic synthetic pheromone, significant numbers of both sexes of R. batesi were attracted in an approximately equal ratio, indicating that the compound is an aggregation-sex pheromone rather than a sex pheromone.
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- 2023
27. Epidemiology, genetics, and risk factors for chronic venous disease
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Fukaya, Eri, primary
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- 2024
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28. $B \to D^*\ell\nu_\ell$ semileptonic form factors from lattice QCD with M\'obius domain-wall quarks
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Aoki, Y., Colquhoun, B., Fukaya, H., Hashimoto, S., Kaneko, T., Kellermann, R., Koponen, J., and Kou, E.
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High Energy Physics - Lattice ,High Energy Physics - Experiment ,High Energy Physics - Phenomenology - Abstract
We calculate the form factors for the $B \to D^*\ell\nu_\ell$ decay in 2+1 flavor lattice QCD. For all quark flavors, we employ the M\"obius domain-wall action, which preserves chiral symmetry to a good precision. Our gauge ensembles are generated at three lattice cutoffs $a^{-1} \sim 2.5$, 3.6 and 4.5 GeV with pion masses as low as $M_\pi \sim 230$ MeV. The physical lattice size $L$ satisfies the condition $M_\pi L \geq 4$ to control finite volume effects (FVEs), while we simulate a smaller size at the smallest $M_\pi$ to directly examine FVEs. The bottom quark masses are chosen in a range from the physical charm quark mass to $0.7 a^{-1}$ to control discretization effects. We extrapolate the form factors to the continuum limit and physical quark masses based on heavy meson chiral perturbation theory at next-to-leading order. Then the recoil parameter dependence is parametrized using a model independent form leading to our estimate of the decay rate ratio between the tau ($\ell = \tau$) and light lepton ($\ell = e,\mu$) channels $R(D^*) = 0.252(22)$ in the Standard Model. A simultaneous fit with recent data from the Belle experiment yields $|V_{cb}| = 39.19(91)\times 10^{-3}$, which is consistent with previous exclusive determinations, and shows good consistency in the kinematical distribution of the differential decay rate between the lattice and experimental data., Comment: 45 pages, 19 figures; v2: version published in PRD
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- 2023
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29. Sign reversal diode effect in superconducting Dayem nanobridges
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Margineda, Daniel, Crippa, Alessandro, Strambini, Elia, Fukaya, Yuri, Mercaldo, Maria Teresa, Cuoco, Mario, and Giazotto, Francesco
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Condensed Matter - Superconductivity ,Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Supercurrent diodes are nonreciprocal electronic elements whose switching current depends on their flow direction. Recently, a variety of composite systems combining different materials and engineered asymmetric superconducting devices have been proposed. Yet, ease of fabrication and tunable sign of supercurrent rectification joined to large efficiency have not been assessed in a single platform so far. We demonstrate that all-metallic superconducting Dayem nanobridges naturally exhibit nonreciprocal supercurrents under an external magnetic field, with a rectification efficiency up to $\sim 27\%$. Our niobium nanostructures are tailored so that the diode polarity can be tuned by varying the amplitude of an out-of-plane magnetic field or the temperature in a regime without magnetic screening. We show that sign reversal of the diode effect may arise from the high-harmonic content of the current phase relation in combination with vortex phase windings present in the bridge or an anomalous phase shift compatible with anisotropic spin-orbit interactions.
- Published
- 2023
30. Experimental visualization of water/ice phase distribution at cold start for practical-sized polymer electrolyte fuel cells
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Higuchi, Yuki, Yoshimune, Wataru, Kato, Satoru, Hibi, Shogo, Setoyama, Daigo, Isegawa, Kazuhisa, Matsumoto, Yoshihiro, Hayashida, Hirotoshi, Nozaki, Hiroshi, Harada, Masashi, Fukaya, Norihiro, Suzuki, Takahisa, Shinohara, Takenao, and Nagai, Yasutaka
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- 2024
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31. C-terminal truncations in IQSEC2: implications for synaptic localization, guanine nucleotide exchange factor activity, and neurological manifestations
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Nakashima, Moeko, Shiroshima, Tomoko, Fukaya, Masahiro, Sugawara, Takeyuki, Sakagami, Hiroyuki, and Yamazawa, Kazuki
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- 2024
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32. Risk factors for venous thrombosis after esophagectomy
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Torii, Naoya, Miyata, Kazushi, Fukaya, Masahide, and Ebata, Tomoki
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- 2024
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33. Traveling waves for a nonlinear Schrödinger system with quadratic interaction
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Fukaya, Noriyoshi, Hayashi, Masayuki, and Inui, Takahisa
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- 2024
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34. Instability of stationary solutions for double power nonlinear Schr\'odinger equations in one dimension
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Fukaya, Noriyoshi and Hayashi, Masayuki
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Mathematics - Analysis of PDEs - Abstract
We consider a double power nonlinear Schr\"odinger equation which possesses the algebraically decaying stationary solution $\phi_0$ as well as exponentially decaying standing waves $e^{i\omega t}\phi_\omega(x)$ with $\omega>0$. It is well-known from the general theory that stability properties of standing waves are determined by the derivative of $\omega\mapsto M(\omega):=\frac{1}{2}\|\phi_\omega\|_{L^2}^2$; namely $e^{i\omega t}\phi_\omega$ with $\omega>0$ is stable if $M'(\omega)>0$ and unstable if $M'(\omega)<0$. However, the stability/instability of stationary solutions is outside the general theory from the viewpoint of spectral properties of linearized operators. In this paper we prove the instability of the stationary solution $\phi_0$ in one dimension under the condition $M'(0):=\lim_{\omega\downarrow 0}M'(\omega)\in[-\infty, 0)$. The key in the proof is the construction of the one-sided derivative of $\omega\mapsto\phi_\omega$ at $\omega=0$, which is effectively used to construct the unstable direction of $\phi_0$., Comment: 26 pages, 2 figures
- Published
- 2023
35. Why magnetic monopole becomes dyon in topological insulators
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Aoki, Shoto, Fukaya, Hidenori, Kan, Naoto, Koshino, Mikito, and Matsuki, Yoshiyuki
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Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Lattice ,High Energy Physics - Theory - Abstract
The Witten effect predicts that a magnetic monopole acquires a fractional electric charge inside topological insulators. In this work, we give a microscopic description of this phenomenon, as well as an analogous two-dimensional system with a vortex. We solve the Dirac equation of electron field both analytically in continuum and numerically on a lattice, by adding the Wilson term and smearing the gauge field within a finite range to regularize the short-distance behavior of the system. Our results reveal that the Wilson term induces a strong positive mass shift, creating a domain-wall around the monopole/vortex. This small, yet finite-sized domain-wall localizes the chiral zero modes and ensures their stability through the Atiyah-Singer index theorem, whose cobordism invariance is crucial in explaining why the electric charge is fractional., Comment: 40 pages, 10 figures, minor corrections, references added, published version
- Published
- 2023
36. Free products of coarsely convex spaces and the coarse Baum-Connes conjecture
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Fukaya, Tomohiro and Matsuka, Takumi
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Mathematics - Metric Geometry ,Primary 51F30, Secondary 20F65, 58B34 - Abstract
The first author and Oguni introduced a wide class of metric spaces, called coarsely convex spaces. It includes Gromov hyperbolic metric spaces, CAT(0) spaces, systolic complexes, proper injective metric spaces. We introduce the notion of free products of metric spaces and show that free products of symmetric geodesic coarsely convex spaces are also symmetric geodesic coarsely convex spaces. As an application, it follows that free products of symmetric geodesic coarsely convex spaces satisfy the coarse Baum-Connes conjecture., Comment: 30 pages, 11 figures
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- 2023
37. Thermodynamics with M\'obius domain wall fermions near physical point II
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Aoki, Sinya, Fukaya, Hidenori, Goswami, Jishnu, Hashimoto, Shoji, Kanamori, Issaku, Kaneko, Takashi, and Zhang, Yu
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High Energy Physics - Lattice - Abstract
We report on our finite temperature 2+1 flavor lattice QCD simulation to study the thermodynamic properties of QCD near the (pseudo) critical point employing $N_T=12$ and $16$. The simulation points are chosen along the lines of constant physics. The quark mass for M\"obius domain-wall fermion are tuned by taking into account the residual mass either by fine-tuning the input quark masses or by post-process using reweighting. In this talk, we focus on simulation details and present some preliminary results., Comment: 8 pages, contribution to the 39th International Symposium on Lattice Field theory (LATTICE2022), 8th-13th August, 2022, Bonn, Germany
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- 2023
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38. Absolute reliability of Young's modulus of the soleus muscle and Achilles tendon measured using shear wave elastography in healthy young males
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Hayato Miyasaka, Bungo Ebihara, Takashi Fukaya, and Hirotaka Mutsuzaki
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Bland–Altman plot ,Minimal detectable change ,Reliability ,Shear wave elastography ,Young's modulus ,Sports medicine ,RC1200-1245 - Abstract
Background: Stiffness of the soleus muscle (SOL) and Achilles tendon (AT) are associated with Achilles tendinitis and medial tibial stress syndrome. Therefore, reliable SOL and AT stiffness measurements are important for monitoring clinical progress. However, little is known about the absolute reliability of the stiffness measurements of SOL and AT in different ankle positions. This study aimed to determine the absolute reliability of the Young's modulus measurements of the SOL and AT in different ankle positions in healthy young males. Methods: This study included 33 healthy young males. SOL and AT stiffnesses were measured using Young's modulus and shear-wave elastography (SWE). Measurements were taken while the participants were kneeling, with their knees flexed to 90°, and the upper body supported by a table. Ultrasound images were recorded at ankle dorsiflexion angles of −10°, 0°, and 10°. The same measurements were repeated 15 min after the first measurement. Bland–Altman plots were used to verify the type or amount of error and 95 % confidence interval of the minimal detectable change (MDC95) values of the measurements. Results: Bland–Altman plots identified that there was no fixed or proportional bias and that there was good agreement between the first- and second-time measurements of the SOL and AT, respectively, among all angles. The MDC95 of the Young's modulus of SOL at −10°, 0°, and 10° of ankle dorsiflexion were 5.6 kPa, 7.0 kPa, and 10.1 kPa, respectively, and AT were 15.8 kPa, 16.4 kPa, and 17.8 kPa, respectively. Conclusion: Young's modulus measurements of the SOL and AT using SWE can be used to quantify elastic properties with high confidence. Clinically, assessing changes in the Young's moduli of the SOL and AT using SWE may help determine the effectiveness of interventions.
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- 2024
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39. Multicenter prospective observational study to clarify the current status and clinical outcome in Japanese patients who have an indication for implantable cardioverter defibrillator (ICD) or wearable cardioverter defibrillator (WCD) (TRANSITION JAPAN‐ICD/WCD study): Rationale and design of a prospective, multicenter, observational, comparative study
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Yukitoshi Ikeya, Yasuo Okumura, Rikitake Kogawa, Koichi Nagashima, Toshiko Nakai, Katsuaki Yokoyama, Kazuki Iso, Takeshi Kato, Toyonobu Tsuda, Eizo Tachibana, Satoshi Hayashida, Hidehira Fukaya, Naruya Ishizue, Hidemori Hayashi, Shunsuke Kuroda, Kazumasa Sonoda, Shiro Nakahara, Yuichi Hori, Masahide Harada, Masato Murakami, Yu‐Ki Iwasaki, Yoshiyasu Aizawa, Wataru Shimizu, Seiji Fukamizu, Mitsuru Takami, Kengo Kusano, Kohei Ishibashi, Tomoo Harada, Ikutaro Nakajima, Haruna Tabuchi, Mitsuhiro Kunimoto, Morio Shoda, Satoshi Higuchi, Itsuro Morishima, Yasunori Kanzaki, Ritsushi Kato, Yoshifumi Ikeda, Hisaki Makimoto, Tomoyuki Kabutoya, Kazuomi Kario, Takanori Arimoto, Yuichi Ninomiya, Issei Yoshimoto, Shingo Sasaki, Yusuke Kondo, Toshinori Chiba, Kennosuke Yamashita, Yosuke Mizuno, Masaru Inoue, Takeshi Ueyama, Jyunjiro Koyama, Takuo Tsurugi, Yoshiya Orita, Taku Asano, Toshiro Shinke, Kaoru Tanno, Kenta Murotani, and For the TRANSITION JAPAN‐ICD/WCD study
- Subjects
heart failure with reduced ejection fraction ,implantable cardioverter defibrillator ,primary prevention ,wearable cardioverter defibrillator ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Despite the positive impact of implantable cardioverter defibrillators (ICDs) and wearable cardioverter defibrillators (WCDs) on prognosis, their implantation is often withheld especially in Japanese heart failure patients with reduced left ventricular ejection fraction (HFrEF) who have not experienced ventricular tachycardia (VT) or ventricular fibrillation (VF) for uncertain reasons. Recent advancements in heart failure (HF) medications have significantly improved the prognosis for HFrEF. Given this context, a critical reassessment of the treatment and prognosis of ICDs and WCDs is essential, as it has the potential to reshape awareness and treatment strategies for these patients. Methods We are initiating a prospective multicenter observational study for HFrEF patients eligible for ICD in primary and secondary prevention, and WCD, regardless of device use, including all consenting patients. Study subjects are to be enrolled from 31 participant hospitals located throughout Japan from April 1, 2023, to December 31, 2024, and each will be followed up for 1 year or more. The planned sample size is 651 cases. The primary endpoint is the rate of cardiac implantable electronic device implementation. Other endpoints include the incidence of VT/VF and sudden death, all‐cause mortality, and HF hospitalization, other events. We will collect clinical background information plus each patient's symptoms, Clinical Frailty Scale score, laboratory test results, echocardiographic and electrocardiographic parameters, and serial changes will also be secondary endpoints. Results Not applicable. Conclusion This study offers invaluable insights into understanding the role of ICD/WCD in Japanese HF patients in the new era of HF medication.
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- 2024
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40. Recurrent episodes of atrioventricular nodal reentrant tachycardia: Sites of ablation success, ablation endpoint, and primary culprits for recurrence
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Shu Hirata, Koichi Nagashima, Yoshiaki Kaneko, Shuntaro Tamura, Hitoshi Mori, Suguru Nishiuchi, Michifumi Tokuda, Tetsuma Kawaji, Tatsuya Hayashi, Takuro Nishimura, Masato Fukunaga, Jun Kishihara, Hidehira Fukaya, Jin Teranishi, Mitsuru Takami, Masato Okada, Naoko Miyazaki, Ryuta Watanabe, Yuji Wakamatsu, and Yasuo Okumura
- Subjects
atrioventricular nodal reentrant tachycardia ,leftward inferior extension ,rightward inferior extension ,slow pathway ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Atrioventricular nodal reentrant tachycardia (AVNRT) sometimes recurs even after anatomical slow pathway (SP) ablation targeting the rightward inferior extension (RIE). This multicenter study aimed to determine the reasons for AVNRT recurrence. Methods and Results Forty‐six patients were treated successfully for recurrent AVNRT. Initial treatment was for 38 slow‐fast AVNRTs, 3 fast‐slow AVNRTs, 2 slow‐slow AVNRTs, 2 slow‐fast and fast‐slow AVNRTs, and 1 noninducible AVNRT. All initial treatments were of RF application to the RIE; SP elimination was achieved in 11, dual AVN physiology was seen in 29, and AVNRT remained inducible in 5. The recurrent AVNRTs included 34 slow‐fast AVNRTs, 6 fast‐slow AVNRTs, 3 slow‐slow AVNRTs, 2 slow‐fast and fast‐slow AVNRTs, and 1 slow‐fast and slow‐slow AVNRTs. Successful ablation site was within the RIE in 39 and left inferior extension in 7. In 30 of 39, the successful RIE site was in the same area or higher than that of the initial procedure. Conclusion For a high majority (around 85%) of patients in whom AVNRT recurs after initial ablation success, the site of a second successful procedure will be within the RIE even though the RIE was originally targeted. Furthermore, a high majority (around 86%) of sites of successful ablation will be higher than those originally targeted.
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- 2024
- Full Text
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41. Dialkyl Carbonate Synthesis Using Atmospheric Pressure of CO2
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Hiroki Koizumi, Haruki Nagae, Katsuhiko Takeuchi, Kazuhiro Matsumoto, Norihisa Fukaya, Yoshiaki Inoue, Satoshi Hamura, Takahiro Masuda, and Jun-Chul Choi
- Subjects
Chemistry ,QD1-999 - Published
- 2024
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42. The Potential Perspective of Processing Rice Husk as SiO2 Source to Tetraalkoxysilane in Indonesia
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Benny Wahyudianto, Wahyu Saptrio Putro, Thuy Thi Hong Nguyen, Norihisa Fukaya, and Sho Kataoka
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indonesia ,rice husk ash ,tetra-alkoxysilane ,Chemistry ,QD1-999 - Abstract
Tetra-alkoxysilane (TROS) is one of the useful chemicals and it can be processed to produce semiconductor and photovoltaic devices. Now, the transformation of silica (SiO2) to TROS is garnering interest due to the potential of extracting it from biomass. As the 14th largest country, Indonesia possesses an abundant source of SiO2 from mining activities and agricultural waste, notably rice husk (RH). However, only a little concrete action is planned for leveraging RH into a more valuable industrial substance. This review will explain two routes for TROS—conventional and direct—comparing their respective benefits and drawbacks. Additionally, it presents a simulation of various scenarios for scaling TROS production to an industrial level, considering technoeconomic and environmental assessment aspects. The focus then shifts to Indonesia’s strategic trajectory for 2045, offering recommendations to enhance resource utilization for economic and national development.
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- 2024
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43. Correction: Visualizing the spatial distribution of ustalic acid in the fruiting body of Tricholoma kakishimeji
- Author
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Ito, Tetsuro, Taira, Shu, Aoki, Wataru, Nagai, Hiroyuki, Fukaya, Masashi, Ryu, Kaori, and Yamada, Akiyoshi
- Published
- 2024
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44. Curved domain-wall fermion and its anomaly inflow
- Author
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Aoki, Shoto and Fukaya, Hidenori
- Subjects
High Energy Physics - Lattice ,Condensed Matter - Mesoscale and Nanoscale Physics ,High Energy Physics - Theory - Abstract
We investigate the effect of $U (1)$ gauge field on lattice fermion systems with a curved domain-wall mass term. In the same way as the conventional flat domain-wall fermion, the chiral edge modes appear localized at the wall, whose Dirac operator contains the induced gravitational potential as well as the $U(1)$ vector potential. In the case of $S^1$ domain-wall fermion on a two-dimensional flat lattice, we find a competition between the Aharonov-Bohm(AB) effect and gravitational gap in the Dirac eigenvalue spectrum, which leads to anomaly of the time-reversal ($T$) symmetry. Our numerical result shows a good consistency with the Atiyah-Patodi-Singer index theorem on a disk inside the $S^1$ domain-wall, which describes the cancellation of the $T$ anomaly between the bulk and edge. When the $U(1)$ flux is squeezed inside one plaquette, and the AB phase takes a quantized value $\pi$ mod $2\pi\mathbb{Z}$, the anomaly inflow drastically changes: the strong flux creates another domain-wall around the flux to make the two zero modes coexist. This phenomenon is also observed in the $S^2$ domain-wall fermion in the presence of a magnetic monopole. We find that the domain-wall creation around the monopole microscopically explains the Witten effect., Comment: 30 pages, 13 figures, minor corrections
- Published
- 2022
45. Twisted magnetic field in star formation processes of L1521 F revealed by submillimeter dual band polarimetry using James Clerk Maxwell Telescope
- Author
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Fukaya, Sakiko, Shinnaga, Hiroko, Furuya, Ray S., Tomisaka, Kohji, Machida, Masahiro N., and Harada, Naoto
- Subjects
Astrophysics - Solar and Stellar Astrophysics - Abstract
Understanding the initial conditions of star formation requires both observational studies and theoretical works taking into account the magnetic field, which plays an important role in star formation processes. Herein, we study the young nearby dense cloud core L1521 F ($n$(H$_2$) $\sim 10^{4-6}$ cm$^{-3}$) in the Taurus Molecular Cloud. This dense core hosts a 0.2 $M_\odot$ protostar, categorized as a Very Low Luminosity Objects with complex velocity structures, particularly in the vicinity of the protostar. To trace the magnetic field within the dense core, we conducted high sensitivity submillimeter polarimetry of the dust continuum at $\lambda$= 850 $\mu$m and 450 $\mu$m using the POL-2 polarimeter situated in front of the SCUBA-2 submillimeter bolometer camera on James Clerk Maxwell Tetescope. This was compared with millimeter polarimetry taken at $\lambda$= 3.3 mm with ALMA. The magnetic field was detected at $\lambda$= 850 $\mu$m in the peripheral region, which is threaded in a north-south direction, while the central region traced at $\lambda$= 450 $\mu$m shows a magnetic field with an east-west direction, i.e., orthogonal to that of the peripheral region. Magnetic field strengths are estimated to be $\sim$70 $\mu$G and 200 $\mu$G in the peripheral- and central-regions, respectively, using the Davis-Chandrasekhar-Fermi method. The resulting mass-to-flux ratio of 3 times larger than that of magnetically critical state for both regions indicates that L1521 F is magnetically supercritical, i.e., gravitational forces dominate over magnetic turbulence forces. Combining observational data with MHD simulations, detailed parameters of the morphological properties of this puzzling object are derived for the first time., Comment: 9 pages, 7 figures
- Published
- 2022
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46. Monotone Lagrangian Floer theory in smooth divisor complements: III
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Daemi, Aliakbar and Fukaya, Kenji
- Subjects
Mathematics - Symplectic Geometry ,Mathematics - Differential Geometry ,53D40, 53D37 - Abstract
This is the third paper in a series of papers studying intersection Floer theory of Lagrangians in the complement of a smooth divisor. We complete the construction of Floer homology for such Lagrangians., Comment: 56 pages, 8 figures. This paper is born out of the revisions of 1808.08915 and 1809.03409, where some parts of the older versions of 1808.08915 and 1809.03409 are moved here. We also added a brief speculative discussion at the end about a generalization of our construction to the case of non-compact Lagrangians and its formal similarity to the definition of monopole Floer homology
- Published
- 2022
47. Drug–drug interactions between letermovir and tacrolimus in Japanese renal transplant recipients simulated using a physiologically based pharmacokinetic model
- Author
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Takumi Maruyama, Hidefumi Kasai, Yutaka Fukaya, Mitsuru Shiokawa, Toshimi Kimura, and Yukihiro Hamada
- Subjects
physiologically based pharmacokinetic modeling ,drug–drug interaction ,letermovir ,tacrolimus ,renal transplantation ,Japanese population ,Microbiology ,QR1-502 - Abstract
Letermovir (LET) is a novel antiviral agent recently approved for cytomegalovirus (CMV) prophylaxis of renal transplant patients in Japan. However, its interactions with tacrolimus (TAC), an important immunosuppressant, remain ambiguous, warranting careful evaluation considering the unique genetic and physiological characteristics of Japanese patients. Therefore, in this study, we aimed to investigate the drug–drug interactions between LET and extended-release TAC (ER-TAC) in Japanese renal transplant patients via physiologically based pharmacokinetic (PBPK) modeling. We developed PBPK models for LET and TAC, including a new model for ER-TAC, using the Simcyp simulator. We also created a virtual Japanese post-transplant population by incorporating physiological parameters specific to Japanese patients, including CYP3A5 genotypes. Our model accurately predicted the pharmacokinetics of both immediate-release and ER-TAC co-administered with LET. In the Japanese population, LET significantly increased ER-TAC exposure, with the effect varying by CYP3A5 genotype. For CYP3A5*1 carrier, the area under the curve ratio ranged from 2.33 to 2.53, while for CYP3A5*3/*3 carriers, it ranged from 2.82 to 2.86. The maximum concentration ratio was approximately 1.50 across all groups. Our findings suggest reducing the ER-TAC dose by approximately 57–60% for CYP3A5*1 carrier and 65% for CYP3A5*3/*3 carriers when co-administered with LET for Japanese renal transplant patients. Moreover, the developed model incorporating population-specific factors, such as hematocrit values and CYP3A5 genotype frequencies, is a valuable tool to evaluate complex drug interactions and guide the dosing strategies for LET and TAC in Japanese patients. Overall, this study expands the application of PBPK modeling in transplant pharmacology, contributing to the development of effective immunosuppressive strategies for Japanese renal transplant patients.
- Published
- 2024
- Full Text
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48. Differences and Relationships Between Teachers’ Pedagogical Beliefs and Teaching Strategies Used at Different School Levels in Japan
- Author
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Mari Fukuda, Tatsushi Fukaya, and Takashi Kusumi
- Subjects
History of scholarship and learning. The humanities ,AZ20-999 ,Social Sciences - Abstract
Existing meta-analyses have shown that active learning strategies are effective in improving students’ learning performance. However, their implementation may vary across school levels. This study investigated differences among elementary, middle, and high school teachers in the use of teaching strategies, including those that promote active learning and pedagogical beliefs. We also explored differences in the relationships between beliefs about teaching and learning, teaching experience, and teaching strategies for active learning across school levels. An online survey was conducted with 550 in-service elementary, middle, and high school teachers. Participants completed a questionnaire that measured their teaching strategies, beliefs about teaching and learning, and teaching experience. The results revealed differences in the frequency of use of six teaching strategies, including those that promoted active learning. Elementary school teachers used teaching strategies that promoted active learning most frequently, followed by middle and high school teachers. There were no differences in teachers’ beliefs about teaching and learning across school levels. Multigroup structural equation modeling indicated no differences in the influence of beliefs about teaching and learning on active learning teaching strategies among school levels, except that the traditional conception was negatively associated with the implementation of active learning in middle school. Constructivist beliefs were positively associated with active learning strategies across all levels, whereas teaching experience was negatively associated with teaching strategies that promoted student output at the higher school level. These findings have implications for the implementation of active learning, particularly at higher school levels.
- Published
- 2024
- Full Text
- View/download PDF
49. A systematic review and meta-analysis of intervention studies on mathematics and science pedagogical content knowledge
- Author
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Tatsushi Fukaya, Daiki Nakamura, Yoshie Kitayama, and Takumi Nakagoshi
- Subjects
pedagogical content knowledge ,intervention ,meta-analysis ,systematic review ,meta-regression analysis ,Education (General) ,L7-991 - Abstract
Pedagogical content knowledge (PCK) has been considered as professional knowledge that teachers need to effectively instruct students. Empirical studies have been conducted to enrich teachers' PCK through interventions such as professional development programs. In this study, we conducted a systematic review and meta-analysis of studies about PCK interventions and their quantitative evaluation among mathematics or science teachers at the elementary and secondary education levels. We identified 101 effect sizes (42 for multiple group comparison designs and 59 for multiple time point comparison designs) and found that the interventions had a positive effect in both designs. The results of the meta-regression analysis showed that in the multiple group design, the effects differed by intervention target, with higher scores for the PCK intervention than for the CK-only intervention, and in the multiple time point design, the effects differed by subjects treated, with higher scores for the science materials than for the mathematics materials. These results not only demonstrate the average effectiveness of previous studies aimed at improving teachers' PCK but also provide insights into effective designs for professional development methods that promote PCK acquisition.Systematic review registrationhttps://osf.io/vf4hq/?view_only=068483e4e82c42cd994e2c8174bd0a64.
- Published
- 2024
- Full Text
- View/download PDF
50. Generation of two iPSC lines from vascular Ehlers-Danlos Syndrome (vEDS) patients carrying a missense mutation in COL3A1 gene
- Author
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Amit Manhas, Dipti Tripathi, Chikage Noishiki, David Wu, Lu Liu, Karim Sallam, Jason T. Lee, Eri Fukaya, and Nazish Sayed
- Subjects
vascular Ehlers-Danlos Syndrome ,Induced pluripotent stem cells ,COL3A1 ,Biology (General) ,QH301-705.5 - Abstract
Vascular Ehlers-Danlos Syndrome (vEDS) is an inherited connective tissue disorder caused by COL3A1 gene, mutations that encodes type III collagen, a crucial component of blood vessels. vEDS can be life-threatening as these patients can have severe internal bleeding due to arterial rupture. Here, we generated induced pluripotent stem cell (iPSC) lines from two vEDS patients carrying a missense mutation in the COL3A1 (c.226A > G, p.Asn76Asp) gene. These lines exhibited typical iPSC characteristics including morphology, expression of pluripotency markers, and could differentiate to all three germ layer. These iPSC lines can serve as valuable tools for elucidating the pathophysiology underlying vEDS.
- Published
- 2024
- Full Text
- View/download PDF
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