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Mechanical stress is involved in the onset of sports-related enthesopathy. Although the amount of exercise undertaken is a recognized problem during disease onset, changes in muscle contraction type are also involved in the increase in mechanical stress during exercise. This study aimed to clarify the effects of increased mechanical stress associated with muscle contraction type and amount of exercise on enthesis. Twenty mice underwent treadmill exercise, and the muscle contraction type and overall load during exercise were adjusted by varying the angle and speed conditions. Histological analysis was used to the cross-sectional area of the muscle; area of the enthesis fibrocartilage (FC), and expression of inflammation-, degeneration-, and calcification-related factors in the FC area. In addition, the volume and structure of the bone and FC area were examined using microcomputer imaging. Molecular biological analysis was conducted to compare relative expression levels of inflammation and cytokine-related factors in tendons. The Overuse group, which increased the amount of exercise, showed no significant differences in parameters compared to the sedentary mice (Control group). The mice subjected to slow-speed downhill running (Misuse group) showed pathological changes compared to the Control and Overuse groups, despite the small amount of exercise. Thus, the enthesis FC area may be altered by local mechanical stress that would be increased by eccentric muscle contraction rather than by mechanical stress that increases with the overall amount of exercise. Clinical Significance: The muscle contraction type might be more involved in the onset of sports-related enthesopathy rather than the amount of exercise.

Purpose Joint instability is a common joint dysfunction and a cause of musculoskeletal disorder and pain after anterior cruciate ligament injury and osteoarthritis. The aim of this literature review is to review the existing evidence regarding the impacts of knee brace in persons with joint instability, or laxity after knee disease concerning physical and functional outcomes. Methods A systematic search was performed at MEDLINE, Central Register of Controlled Trials (CENTRAL), PubMed, and PEDro and Web of Science databases until April 2, 2022, with their language limited to English. Studies to be included were randomized controlled trials (RCTs), controlled clinical trials, and controlled experimental studies that included comparison of interventions and no interventions testing effectiveness of orthotics in joint instability symptom patients Results Total 250 studies were retrieved and 12 articles met the inclusion criteria. Beneficial effects of knee braces appear to vary with disease. Self-reported instability may be improved with orthotics, while its effects are unclear in an objective assessment of joint instability. However, improved subjective instability lead to improved physical function. Conclusion Our aim is to provide information to both healthcare professionals with updated and high-quality recommendations for the management of instability joint condition. It is concluded that orthotic therapy may have a certain effect on subjective evaluation in joint instability.

Cartilage degeneration is the main pathological component of knee osteoarthritis (OA), but no effective treatment for its control exists. Although exercise can inhibit OA, the abnormal joint movement with knee OA must be managed to perform exercise. Our aims were to determine how controlling abnormal joint movement and treadmill exercise can suppress cartilage degeneration, to analyze the tissues surrounding articular cartilage, and to clarify the effect of treatment. Twelve-week-old ICR mice (n = 24) underwent anterior cruciate ligament transection (ACL-T) surgery on their right knees and were divided into three groups as follows: ACL-T, animals in the walking group subjected to ACL-T, controlled abnormal joint movement (CAJM), and CAJM with exercise (CAJM + Ex) (n = 8/group). Walking-group animals were subjected to treadmill exercise 6 weeks after surgery, including walking for 18 m/min, 30 min/day, 3 days/week for 8 weeks. Safranin-O staining, hematoxylin-eosin staining, and immunohistochemical staining were performed. The OARSI (Osteoarthritis research Society international) score was lower in the CAJM group than in the ACL-T group and was even lower in the CAJM + Ex group. The CAJM group had a lower meniscal injury score than the ACL-T group, and the CAJM + Ex group demonstrated a less severe synovitis than the ACL-T and CAJM groups. The observed difference in the perichondrium tissue damage score depending on the intervention method suggests different therapeutic effects, that normalizing joint motion can solve local problems in the knee joint, and that the anti-inflammatory effect of treadmill exercise can suppress cartilage degeneration.

The healing ability of the anterior cruciate ligament (ACL) injury is very poor; however, it has recently been shown to undergo self-healing with conservative treatments. In this study, we evaluated the influence of the site of injury on the healing process after complete transverse tear of ACL using a rat model.A total of 58 skeletally mature Wistar rats were randomly assigned to various ACL injury groups: controlled abnormal movement-mid-portion (CAM-MP), controlled abnormal movement-femoral side (CAM-FS), ACL transection-mid-portion (ACLT-MP), or ACL transection-femoral side (ACLT-FS) injury groups. The ACL was completely transected in the mid-portion in the ACLT-MP and CAM-MP groups, and on the femoral side in the ACLT-FS and CAM-FS groups. Both CAM groups underwent extra-articular braking to control for abnormal tibial translation. The animals were allowed full cage activity until sacrifice postoperatively for histological and biomechanical assessment.Significant differences were found in the ratios of residual ligament lengths between the CAM-MP and CAM-FS groups, demonstrating the validity of each model. Spontaneous healing of the injured ACL was observed in the CAM-MP and CAM-FS groups but not in the ACLT-MP and ACLT-FS groups. The mechanical strength of the healing ACL did not differ between the CAM-MP and CAM-FS groups 8 weeks after injury; however, the former had better mechanical strength than the latter 12 weeks after the injury.ACL injuries in the mid-portion and on the femoral side may be treated with conservative therapy for spontaneous healing.

Objective Moderate mechanical stress is necessary for preserving the cartilage. The clinician empirically understands that prescribing only exercise will progress osteoarthritis (OA) for knee OA patients with abnormal joint movement. When prescribing exercise for OA, we hypothesized that degeneration of articular cartilage could be further prevented by combining interventions with the viewpoint of normalizing joint movement. Design Twelve-week-old ICR mice underwent anterior cruciate ligament transection (ACL-T) surgery in their right knee and divided into 4 groups: ACL-T, controlled abnormal joint movement (CAJM), ACL-T with exercise (ACL-T/Ex), CAJM with exercise (CAJM/Ex). Animals in the walking group were subjected to treadmill exercise 6 weeks after surgery, which included walking for 18 m/min, 30 min/d, 3 d/wk for 4 weeks. Joint instability was measured by anterior drawer test, and safranin-O staining and immunohistochemical staining were performed. Results OARSI (Osteoarthritis Research Society International) score of ACL-T/Ex group showed highest among 4 groups ( P < 0.001). And CAJM/Ex group was lower than ACL-T/Ex group. Positive cell ratio of IL-1β and MMP-13 in CAJM/Ex group was lower than ACL-T/Ex group ( P < 0.05). Conclusions We found that the state of the intra-articular environment can greatly influence the effect of exercise on cartilage degeneration, even if exercise is performed under the same conditions. In the CAJM/Ex group where joint movement was normalized, abnormal mechanical stress such as shear force and compression force accompanying ACL cutting was alleviated. These findings may highlight the need to consider an intervention to correct abnormal joint movement before prescribing physical exercise in the treatment of OA.

Summary Objective Abnormal joint instability contributes to cartilage damage and osteophyte formation. We investigated whether controlling joint instability inhibited chronic synovial membrane inflammation and delayed osteophyte formation and examined the role of transforming growth factor-beta (TGF-β) signaling in the associated mechanism. Design Rats (n = 94) underwent anterior cruciate ligament (ACL) transection. Anterior tibial instability was either controlled (CAM group) or allowed to continue (SHAM group). At 2, 4, and 8 weeks after surgery, radiologic, histopathologic, immunohistochemical, immunofluorescent, and enzyme-linked immunosorbent assay examinations were performed to evaluate osteophyte formation and TGF-β signaling. Results Joint instability increased cartilage degeneration score and osteophyte formation, and cell hyperplasia and proliferation and synovial thickening were observed in the synovial membrane. Major findings were increased TGF-β expression and Smad2/3 following TGF-β phosphorylation in synovial membarene, articular cartilage, and the posterior tibial growth plate (TGF-β expression using ELISA: 4 weeks; P = 0.009, 95% CI [260.1–1340.0]) (p-Smad2/3 expression density: 4 weeks; P = 0.024, 95% CI [1.67–18.27], 8 weeks; P = 0.034, 95% CI [1.25–25.34]). However, bone morphogenetic protein (BMP)-2 and Smad1/5/8 levels were not difference between the SHAM model and the CAM model. Conclusions This study showed that the difference between anterior tibial instability caused a change in the expression level of TGF in the posterior tibia and synovial membrane, and the reaction might be consequently involved in osteophyte formation.

We numerically study quantum effects in intrinsic Josephson junctions of layered high- T c superconductors in order to explain recent experimental observations on the switching rate enhancement in the low temperature quantum regime. We pay attention to the capacitive coupling between neighboring junctions and perform simulations for the Schrodinger equation derived from the Hamiltonian describing the capacitive coupling. The simulation results reveal that the phase dynamics show synchronous behaviors when entering the quantum regime. This is qualitatively consistent with the experimental result.

A new conservative global gyrokinetic toroidal full-f five-dimensional Vlasov simulation (GT5D) is developed using a novel non-dissipative conservative finite difference scheme. The scheme guarantees numerical stability by satisfying relevant first principles in the modern gyrokinetic theory, and enables robust and accurate simulations of tokamak micro-turbulence. GT5D is verified through comparisons of zonal flow damping tests, linear analyses of ion temperature gradient driven (ITG) modes, and nonlinear ITG turbulence simulations against a global gyrokinetic toroidal δf particle code. In the comparison, global solutions of the ITG turbulence are identified quantitatively by using two gyrokinetic codes based on particle and mesh approaches.

We investigate quantum dynamics of the superconducting phase in intrinsic Josephson junctions of layered high- T c superconductors motivated by a recent experimental observation for the switching rate enhancement in the low temperature quantum regime. We pay attention to only the capacitive coupling between neighboring junctions and perform large-scale simulations for the Schrodinger equation derived from the Hamiltonian considering the capacitive coupling alone. The simulation focuses on an issue whether the switching of a junction induces those of the other junctions or not. The results reveal that the superconducting phase dynamics show synchronous behavior with increasing the quantum character, e.g., decreasing the junction plane area and effectively the temperature. This is qualitatively consistent with the experimental result.

The superconducting neutron detector using high-quality 10B-enriched MgB2 thin films at higher operating temperatures has been proposed, where a resistance change induced by the nuclear reaction of neutron and 10B in MgB2 is used to detect a neutron. Cold neutrons from a nuclear research reactor irradiated the MgB2 detector, and the output voltage was clearly observed through a low-noise amplifier by using a digital oscilloscope. The out-of-equilibrium thermodynamics was investigated by means of the time-dependent Ginzburg-Landau equations by using the Earth Simulator.

We perform large-scale numerical simulations on the non-equilibrium superconducting dynamics after a neutron capture at the superconducting transition edge in MgB2 by solving the time-dependent Ginzburg-Landau equation coupled with the Maxwell and the heat diffusion equations. The simulations are carried out under the current-biased condition in order to explain experimental results made in the JAEA reactor JRR-3, and the time scale of the obtained voltage signal is found to be almost consistent with the experiments. Moreover, the time evolution of the voltage signal is connected with that of the spatial profile of the superconducting order parameter.

A low Pr number fluid flow, such as liquid-metals, has relatively less than turbulent heat transport capability because of the liquid-metals’ high thermal conductivity and its very large thermal boundary layer. Liquid-metals as coolant material in fusion reactor have a significant role in the design of advanced reactors. This is true since the investigation of thermal behavior in the actual facility environment such as in the case of low Pr number fluid flow, is needed at high Reynolds number under a magnetic field. In the present study, a direct numerical simulation (DNS) for the low Pr number fluid flow of turbulent heat transfer with high Reynolds number has been carried out to show the effects of magnetic field. The Reynolds number for channel flow based on bulk velocity U b , viscosity ν, and channel width 2 δ was set to be constant as Re b = 2 δU b /ν = 45,818. A uniform magnetic field was applied in a direction perpendicular to the wall of the channel. The values of Hartmann number Ha were 0 and 65 (where H a = 2 δ B 0 σ / ρ ν ), and Prandtl number was 0.06. The turbulent quantities such as the mean temperature, turbulent heat flux, and temperature variant were obtained by DNS. Although large-scale turbulent structures of both velocity and temperature fields are found at the central region of the channel, the mean temperature profiles near wall region show up as laminar profile, that is, the thermal efficiency of the transport is less than that of turbulent flow. This means that it is necessary to consider the fusion reactor design of thermal mixing argumentation for low Pr number fluid flow because the heat transfer enhancement at turbulent flow cannot be acceptable even where the flow state happens to be a turbulent flow at high Reynolds number.

We perform numerical simulations on heat diffusion induced by a nuclear reaction between a neutron and a Boron isotope 10B and related non-equilibrium superconducting dynamics in MgB2 neutron detector devices. The simulation results reveal that not the heat diffusion but the superconducting dynamics caused by the heat diffusion is responsible for the electrical signal. This is because the generated electrical field is directly related with not the local temperature but the phase dynamics of the superconducting macroscopic wave-function. This fact tells us how to improve the neutron detection speed.

We numerically investigate a dependence of pairing interaction strength on quantum coherence and related tunneling dynamics in order to clarify whether the strong pairing interaction suppresses quantum coherent characters. The simulation is performed by using the attractive Hubbard model with double well potential. The simulation result reveals that the tunneling dynamics between the separated wells is dramatically suppressed with increasing the pairing interaction. This fact implies that the pair coherence is easily lost under randomness when the pairing interaction becomes very strong. We claim that such an issue is related to the loss of the pair coherence in under-doped High- T c superconductors. In addition, we note that the tunneling dynamics can be directly confirmed by using the crossover from BCS to BEC in atomic Fermi gases.

In $2048^3$ simulation of quantum turbulence within the Gross-Pitaevskii equation we demonstrate that the large scale motions have a classical Kolmogorov-1941 energy spectrum E(k) ~ k^{-5/3}, followed by an energy accumulation with E(k) ~ const at k about the reciprocal mean intervortex distance. This behavior was predicted by the L'vov-Nazarenko-Rudenko bottleneck model of gradual eddy-wave crossover [J. Low Temp. Phys. 153, 140-161 (2008)], further developed in the paper., Comment: (re)submitted to PRB: 5.5 pages, 4 figures

In order to study quantum many-body problems, we develop two matrix diagonalization codes, which solve only the ground state and all quantum states, respectively. The target model in both codes is the Hubbard model with confinement potential which describes an atomic Fermi gas loaded on an optical lattice and partly High-Tc cuprate superconductor. For the former code, we obtain 18.692TFlops (57% of the peak) as the best performance on the Earth Simulator when calculating the ground state of 100-billion dimensional matrix. From these large-scale calculations, we find atomic-scale inhomogeneous superfluid state which is now a challenging subject for physicists. For the latter code, we succeed in solving the matrix whose dimension is 375,000 with locally 24.6TFlops (75% of the peak). The calculations reveal that a change from Schrodinger's cat to classical like one can be controlled by tuning the interaction. This is a marked contrast to the general concept.