Numerical evaluation of wearing pressure and cloth stiffness on vibration of human skeletal muscle during athletic movement

In the design of sportswear which is expected to modify the performance of athletes, it is important to clarify the effects of the wear's rigidity and wearing pressure on the vibrations during exercise because they have been considered to reduce the vibrations of muscles. Therefore, in this study, the relationship between the vibration generated in cyclic movement of thigh with cloth and the physical properties of the wearing cloth is discussed by using a simple FE model of thigh [1, 2]. In the analysis, the FE model consisted of three parts of the thigh muscle, the femur, and the wear in the cross section of thigh. The thigh muscle is fixed to the femur but it is in contact with the wear cloth ignoring friction. The condition of the thigh cyclical movement is set assuming the athlete's 100 m run. Numerical analysis is performed under these conditions, and the variations of vibration behavior due to changing values of muscle, wear and pressure are evaluated by mechanical consideration. In the results of this FE analysis, it is quantitatively confirmed that more flexible cloth has the effect of restraining vibration, and also its effect can also be observed by applying wearing pressure to thigh

Renormalization group flow and fixed-point in tensor network representations

In this thesis, we present a novel method combining energy-based finite-size scaling with tensor network renormalization (TNR) to study phase transitions in lattice models. This approach effectively calculates running coupling constants and reduces the numerical errors typically associated with TNR, thus requiring fewer renormalization group (RG) steps and less computational resources. Our methodology, contrasting with traditional methods, doesn't depend on large system sizes, making it efficient and robust against simulation scale challenges. We also explore the origins of numerical errors in TNR from a field-theoretical perspective, focusing on how these errors scale with the approximation parameter $D$. This understanding is crucial for error management in simulations. Moreover, we investigate the tensor structure of fixed points in lattice models, addressing challenges from finite bond dimensions using an analytical approach involving conformal mappings. We discover that the tensor elements of fixed-point tensors align with four-point functions of primary operators in conformal field theory (CFT), demonstrating a significant link between CFT and lattice models. This finding underscores the universality of non-trivial infrared physics at the lattice level, bridging theoretical concepts with practical computations in lattice models, and offering deeper insights into the universal aspects of critical phenomena.Comment: Dissertation submitted to Department of Physics, University of Tokyo (Dec. 2023

Quantum State Engineering using Single Nuclear Spin Qubit of Optically Manipulated Ytterbium Atom

A single Yb atom is loaded into a high-finesse optical cavity with a moving lattice, and its nuclear spin state is manipulated using a nuclear magnetic resonance technique. A highly reliable quantum state control with fidelity and purity greater than 0.98 and 0.96, respectively, is confirmed by the full quantum state tomography; a projective measurement with high speed (500us) and high efficiency (0.98) is accomplished using the cavity QED technique. Because a hyperfine coupling is induced only when the projective measurement is operational, the long coherence times (T_1 = 0.49 s and T_2 = 0.10 s) are maintained. Our technique can be applied for implementing a scalable one-way quantum computation with a cluster state in an optical lattice.Comment: 4 figure

Calabi--Yau complete intersections in exceptional Grassmannians

We classify completely reducible equivariant vector bundles on Grassmannians of exceptional Lie groups which give Calabi--Yau 3-folds as complete intersections. In particular, we find a new family of Calabi--Yau 3-folds in an $E_6$-Grassmannian.Comment: 10 pages, minor revisio

Resolving the Berezinskii-Kosterlitz-Thouless transition in the 2D XY model with tensor-network based level spectroscopy

Berezinskii-Kosterlitz-Thouless transition of the classical XY model is re-investigated, combining the Tensor Network Renormalization (TNR) and the Level Spectroscopy method based on the finite-size scaling of the Conformal Field Theory. By systematically analyzing the spectrum of the transfer matrix of the systems of various moderate sizes which can be accurately handled with a finite bond dimension, we determine the critical point removing the logarithmic corrections. This improves the accuracy by an order of magnitude over previous studies including those utilizing TNR. Our analysis also gives a visualization of the celebrated Kosterlitz Renormalization Group flow based on the numerical data

Identification of a nerve ending-enriched 29-kDa protein, labeled with [3- 32 P]1,3-bisphosphoglycerate, as monophosphoglycerate mutase: inhibition by fructose-2,6-bisphosphate via enhancement of dephosphorylation

Glucose metabolism is of vital importance in normal brain function. Evidence indicates that glycolysis, in addition to production of ATP, plays an important role in maintaining normal synaptic function. In an effort to understand the potential involvement of a glycolytic intermediate(s) in synaptic function, we have prepared [3- 32 P]1,3-bisphosphoglycerate and [ 32 P]3-phosphoglycerate and sought their interaction with a specific nerve-ending protein. We have found that a 29-kDa protein is the major component labeled with either [3- 32 P]1,3-bisphosphoglycerate or [ 32 P]3-phosphoglycerate. The protein was identified as monophosphoglycerate mutase (PGAM). This labeling was remarkably high in the brain and synaptosomal cytosol fraction, consistent with the importance of glycolysis in synaptic function. Of interest, fructose-2,6-bisphosphate (Fru-2,6-P 2 ) inhibited PGAM phosphorylation and enzyme activity. Moreover, Fru-2,6-P 2 potently stimulated release of [ 32 P]phosphate from the 32 P-labeled PGAM (EC 50  = 1 µm), suggesting that apparent reduction of PGAM phosphorylation and enzyme activity by Fru-2,6-P 2 may be due to stimulation of dephosphorylation of PGAM. The significance of these findings is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65158/1/j.1471-4159.2003.01777.x.pd