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Osteoarthritis (OA) is the most common joint disease, and good therapeutic results are often difficult to obtain due to its complex pathogenesis and diverse causative factors. After decades of research and exploration of OA, it has been progressively found that subchondral bone is essential for its pathogenesis, and pathological changes in subchondral bone can be observed even before cartilage lesions develop. Osteoclasts, the main cells regulating bone resorption, play a crucial role in the pathogenesis of subchondral bone. Subchondral osteoclasts regulate the homeostasis of subchondral bone through the secretion of degradative enzymes, immunomodulation, and cell signaling pathways. In OA, osteoclasts are overactivated by autophagy, ncRNAs, and Rankl/Rank/OPG signaling pathways. Excessive bone resorption disrupts the balance of bone remodeling, leading to increased subchondral bone loss, decreased bone mineral density and consequent structural damage to articular cartilage and joint pain. With increased understanding of bone biology and targeted therapies, researchers have found that the activity and function of subchondral osteoclasts are affected by multiple pathways. In this review, we summarize the roles and mechanisms of subchondral osteoclasts in OA, enumerate the latest advances in subchondral osteoclast-targeted therapy for OA, and look forward to the future trends of subchondral osteoclast-targeted therapies in clinical applications to fill the gaps in the current knowledge of OA treatment and to develop new therapeutic strategies.

BackgroundIon cyclotron range of frequencies (ICRF) heating is one of the most widely used auxiliary heating methods in tokamaks. The HL-3 tokamak plans to equip a 6 MW ICRF heating system to conduct discharge experiments of high-performance plasma.PurposeThis study optimizes the parameters of ICRF using numerical simulations with the purpose of supporting the reactor-level plasma in HL-3 in future.MethodsOn the basis of NBI heating in the HL-3 device, ICRF heating was considered, and the TRANSP code was employed to explore the influence of ICRF frequency and power in HL-3 on the neutron emission rate, as well as the distribution of fast ions. The ICRF frequency range was between 25 MHz and 40 MHz, and the ICRF power range was between 1 MW and 6 MW. The neutron signals based on the concept of neutron camera diagnosis were also simulated.ResultsThe simulation results show that the ICRF frequency and power significantly influence the neutron emission rate. The neutron emission rate is directly proportional to the ICRF heating power at a fixed ICRF frequency whilst the increase in the neutron emission rate significantly depends on the ICRF frequency when the ICRF heating power is fixed. Among the investigated parameters, the ICRF with a frequency of 30 MHz yields the maximum increase in the neutron emission rate. The simulation results of fast ions demonstrate that the synergetic heating of neutral beam injection and ICRF can heat fast ions up to 1 MeV after considering ICRF heating, which effectively increases the neutron emission rate. The simulation results of neutron camera indicate that neutron camera can effectively measure the changes in neutron emission rate and distribution profile caused by ICRF heating.ConclusionsThe simulation results demonstrate that the appropriate selection of the ICRF frequency and power can effectively increase the neutron emission rate in HL-3 experiments, the optimal combination of ICRF frequency/power is 30 MHz/6 MW for the scenario analyzed in this study. The simulation of neutron camera for HL-3 provides a reference for designing future neutron camera systems and measuring neutron spatial distributions.

A European project was undertaken to improve the available SOL ICRF physics simulation tools and confront them with measurements. This paper first reviews code upgrades within the project. Using the multi-physics finite element solver COMSOL, the SSWICH code couples RF full-wave propagation with DC plasma biasing over “antenna-scale” 2D (toroidal/radial) domains, via non-linear RF and DC sheath boundary conditions (SBCs) applied at shaped plasma-facing boundaries. For the different modules and associated SBCs, more elaborate basic research in RF-sheath physics, SOL turbulent transport and applied mathematics, generally over smaller spatial scales, guides code improvement. The available simulation tools were applied to interpret experimental observations on various tokamaks. We focus on robust qualitative results common to several devices: the spatial distribution of RF-induced DC bias; left-right asymmetries over strap power unbalance; parametric dependence and antenna electrical tuning; DC SOL biasing far from the antennas, and RF-induced density modifications. From these results we try to identify the relevant physical ingredients necessary to reproduce the measurements, e.g. accurate radiated field maps from 3D antenna codes, spatial proximity effects from wave evanescence in the near RF field, or DC current transport. Pending issues towards quantitative predictions are also outlined.

In order to overcome some shortcomings including the premature convergence and slow convergence speed at later evolution stage of conventional cuckoo search (CS) algorithm for the sidelobe suppressions of antenna arrays, an improved CS with reverse learning and invasive weed operators (ICSRLIWO) is proposed. First, ICSRLIWO algorithm generates reverse populations through opposition‐based learning method, then selects better individuals in the mixed population consists of the original and reversed population to form a high‐quality initial population. Second, ICSRLIWO introduces the reproducing, space diffusion and survival competition operators of invasive weed optimization to improve the population diversity and global search ability of conventional CS algorithm. Simulations are conducted based on 30 test functions in the CEC 2014 test suit to verify the performance of the proposed approach, and the results show that ICSRLIWO has higher solution accuracy and faster convergence speed than other comparison algorithms. In addition, ICSRLIWO also has advantages in solving the array antenna beam pattern optimization problems. [ABSTRACT FROM AUTHOR]

The article gathers Chinese records of the Venus transit of 1874 which include prediction observation and astrological discussion. According to the article, the Venus transit is significant in the measurement of the distance between the sun and the earth. It is stated that the transit happened in 1874 and was only visible in China and other locations in eastern sphere.

Osteoarthritis (OA) is a prevalent cause of joint algesia, loss of function, and disability in adults, with cartilage injury being its core pathological manifestation. Since cartilage damage is non-renewable, the treatment outcome in the middle and late stages of OA is unsatisfactory, which can be minimized by changing lifestyle and other treatment modalities if diagnosed and managed in the early stages, indicating the importance of early diagnosis and monitoring of cartilage injury. Ultrasound technology has been used for timely diagnosis and even cartilage injury treatment, which is convenient and safe for the patient owing to no radiation exposure. Studies have demonstrated the effectiveness of ultrasound and its various quantitative ultrasound parameters, like ultrasound roughness index (URI), reflection coefficient (R), apparent integrated backscatter (AIB), thickness, and ultrasound elastography, in the early and accurate assessment of OA cartilage pathological changes, including surface and internal tissue, hardness, and thickness. Although many challenges are faced in the clinical application of this technology in diagnosis, ultrasound and ultrasound-assisted techniques offer a lot of promise for detecting early cartilage damage in OA. In this review, we have discussed the evaluation of ultrasonic cartilage quantitative parameters for early pathological cartilage changes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhang, Ning, Lu, Zhou, Shao, Yang and Hao.)

In magnetic resonance examination, the interaction between implants and the radio frequency (RF) fields induces heating in human tissue and may cause tissue damage. To assess the RF-induced heating of implants, three steps should be executed, including electromagnetic model construction, electromagnetic model validation, and virtual human body simulations. The crucial step of assessing RF-induced heating involves the construction of a test environment for electromagnetic model validation. In this study, a hardware environment, comprised of a RF generation system, electromagnetic field measurement system, and a robotic arm positioning system, was established. Furthermore, an automated control software environment was developed using a Python-based software development platform to enable the creation of a high-precision automated integrated test environment. The results indicate that the electric field generated in this test environment aligns well with the simulated electric field, making it suitable for assessing the RF-induced heating effects of implants.

Background: In 2021, the U.S. Food and Drug Administration (FDA) approved paired vagus nerve stimulation (VNS) for patients with moderate-to-severe upper extremity motor impairments following chronic ischemic stroke., Objective: Previous meta-analyses have shown that VNS may impact stroke rehabilitation, but each has some limitations., Methods: PubMed, Ovid, Cochrane Library, ScienceDirect, Web of Science and WHO ICTRP databases were searched until July 14, 2022 for randomized controlled trials (RCTs). We defined primary outcomes as Fugl-Meyer Assessment for Upper Extremity (FMA-UE) and Wolf Motor Function Test (WMFT). Subgroup analyses included types of VNS, time since onset and long-term effects. Secondary outcomes included adverse events of VNS., Results: Eight RCTs involving 266 patients were analyzed, of which five used direct VNS and three transcutaneous auricular VNS. The results revealed that VNS enhanced upper extremity function via FMA-UE (SMD = 0.73; 95% CI: 0.48 to 0.99; P < 0.00001) and WMFT (SMD = 0.82; 95% CI:0.52 to 1.13; P < 0.00001) in comparison to the control group, but showed no significant change on long-term effects of FMA-UE (SMD = 0.69; 95% CI: - 0.06 to 1.44; P = 0.07). There was no difference in adverse events between the VNS and control groups (RR = 1.16; 95% CI: 0.46 to 2.92; P = 0.74)., Conclusion: For stroke victims with upper limb disabilities, VNS paired with rehabilitation was significantly safe and effective. More high-quality multicentric RCTs are needed to validate this conclusion.

Aiming at the ECG performance indicators in the YY 0885-2013 "Medical electrical equipment Part 2: Particular requirements for the safety including essential performance of ambulatory electrocardiographic systems", the traditional detection methods are time-consuming and the test results are greatly affected by human factors. In this paper, an automated detection method is proposed. A set of automatic detection software for ECG performance is designed and developed based on a single-channel ECG recorder, and an automated detection system is set up in combination with standard testing equipment. And then, the MSA tool is used to analyze the repeatability and stability of the detection system, and the results show that the detection system is acceptable, and it can improve detection efficiency.