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In order to further improve the load-bearing performance of the RV reducer, a force analysis is conducted on the cycloidal pin wheel pair, regarding the contact stress and meshing stiffness of the cycloidal pin wheel as the research objective functions. In order to optimize its load-bearing performance, a mathematical analysis model of contact stress and meshing stiffness is proposed regarding the important structural parameters of cycloidal and pin wheel, as the design variables such as needle tooth distribution circle radius, eccentricity, and needle tooth radius, VB.NET Software is applied to calculate and analyzes the influence of structural parameters of the cycloidal and pin wheel on the meshing stiffness, contact stress, meshing force, and torsional stiffness of the cycloidal and pin wheel pair. The results of calculation and simulation indicate that the meshing stiffness and torsional stiffness of cycloidal and pin wheel increase with the increase of the radius of the distribution circle and eccentricity the decrease of the radius of the teeth. The research provides theoretical foundation for the design and optimization of the structure of cycloidal and pin wheel reducers.

The cycloid gear is the key component of the RV reducer, and the hole structure of the cycloid gear has a great influence on the transmission stability of the of the RV reducer. Based on the meshing contact analysis between the cycloid gear and pin of transmission system, the number of actual meshing teeth pairs of the cycloid gear were obtained. The meshing angle of each tooth pair and the comprehensive meshing stiffness were calculated. Taking the comprehensive meshing stiffness as elastic constraint condition in finite element software, the dynamics harmonic resonance analysis of cycloid gear was carried out. The position of maximum vibration and deformation is located at the fan-shaped lightening hole of cycloid gear plate. According to the different shape of fan-shaped holes of cycloid gear, the dynamics simulation was carried out by orthogonal test with three factors and four levels. The results show that the radius of the top and bottom circle of the fan-shaped hole is always the key factor to the vibration of the cycloidal wheel with the increase of rotation speed, while the vibration increases gradually for the radius of the inverted circle, and decreases for the angle between the waist and the waist. The conclusions are helpful for the structure design of cycloid gear wheel.

Inflammatory osteolysis is often caused by the excessive activation of osteoclasts stimulated by bacterial products such as lipopolysaccharide. The natural flavonoid trifolirhizin (TRI) has anti‐inflammatory properties; however, its function in inflammatory bone lysis remains unclear. This study aimed to elucidate the potential regulatory mechanisms of TRI in osteoclasts.Tartrate‐resistant acid phosphatase (TRAP) staining, acid secretion assays, podosomal actin belt fluorescence staining, and bone resorption assays were used to investigate the effects of TRI on osteoclast differentiation and bone resorption. A reactive oxygen species (ROS) measurement kit was used to detect the effect of TRI on ROS levels in osteoclasts. The effects of TRI on genes and signaling pathways related to osteoclast differentiation were determined by quantitative polymerase chain reaction (qPCR) and western blotting. A mouse model of lipopolysaccharide‐mediated inflammatory osteolysis was established, and the effects of TRI treatment on bone mass were observed using micro‐CT and histological examination. Mechanistically, TRI reduced ROS production by inhibiting receptor activator of nuclear factor‐κB ligand (RANKL)‐induced activation of the nuclear factor‐κB (NF‐κB) and mitogen‐activated protein kinase (MAPK) signaling pathways, and by upregulating the expression levels of the anti‐ROS enzymes heme oxygenase‐1 (HO‐1) and catalase (CAT), which contributed to the degradation of ROS, ultimately leading to a decrease in osteoclastogenesis. TRI inhibited osteoclast formation and ameliorated lipopolysaccharide (LPS)‐mediated inflammatory osteolysis. Thus, TRI may be a candidate agent for anti‐inflammatory osteolysis. [ABSTRACT FROM AUTHOR]

Macrophages are generally assumed to unload surplus cholesterol through direct interactions between ABC transporters on the plasma membrane and HDLs, but they have also been reported to release cholesterol-containing particles. How macrophage-derived particles are formed and released has not been clear. To understand the genesis of macrophage-derived particles, we imaged mouse macrophages by EM and nanoscale secondary ion mass spectrometry (nanoSIMS). By scanning EM, we found that large numbers of 20- to 120-nm particles are released from the fingerlike projections (filopodia) of macrophages. These particles attach to the substrate, forming a "lawn" of particles surrounding macrophages. By nanoSIMS imaging we showed that these particles are enriched in the mobile and metabolically active accessible pool of cholesterol (detectable by ALO-D4, a modified version of a cholesterol-binding cytolysin). The cholesterol content of macrophage-derived particles was increased by loading the cells with cholesterol or by adding LXR and RXR agonists to the cell-culture medium. Incubating macrophages with HDL reduced the cholesterol content of macrophage-derived particles. We propose that release of accessible cholesterol-rich particles from the macrophage plasma membrane could assist in disposing of surplus cholesterol and increase the efficiency of cholesterol movement to HDL.

Spiral ganglia neurons (SGNs) impairment can cause deafness. One important therapeutic approach involves utilizing stem cells to restore impaired auditory circuitry. Nevertheless, the inadequate implementation of research methodologies poses a challenge in accurately assessing the functionality of derived cells within the circuit. Here, we describe a novel method for converting human embryonic stem cells (hESCs) into otic neurons (ONs) and assess their functional connectivity using an optogenetic approach with cells or an organotypic slice of rat cochlear nucleus (CN) in coculture. Embryonic stem cell-derived otic neurons (eONs) exhibited SGN marker expression and generated functional synaptic connection when cocultured with cochlear nucleus neurons (CNNs). Synapsin 1 and VGLUT expression are found in the cochlear nucleus of brain slices, where eONs projected processes during the coculture of eONs and CN brain slices. Action potential spikes and INa+/IK+ of CNNs increased in tandem with light stimulations to eONs. These findings provide further evidence that eONs may be a candidate source to treat SGN-deafness. [ABSTRACT FROM AUTHOR]

Bone metabolism is a process in which osteoclasts continuously clear old bone and osteoblasts form osteoid and mineralization within basic multicellular units, which are in a dynamic balance. The process of bone metabolism is affected by many factors, including diet. Reasonable dietary patterns play a vital role in the prevention and treatment of bone-related diseases. In recent years, dietary patterns have changed dramatically. With the continuous improvement in the quality of life, high amounts of sugar, fat and protein have become a part of people's daily diets. However, people have gradually realized the importance of a healthy diet, intermittent fasting, calorie restriction, a vegetarian diet, and moderate exercise. Although these dietary patterns have traditionally been considered healthy, their true impact on bone health are still unclear. Studies have found that caloric restriction and a vegetarian diet can reduce bone mass, the negative impact of a high-sugar and high-fat dietary (HSFD) pattern on bone health is far greater than the positive impact of the mechanical load, and the relationship between a high-protein diet (HPD) and bone health remains controversial. Calcium, vitamin D, and dairy products play an important role in preventing bone loss. In this article, we further explore the relationship between different dietary patterns and bone health, and provide a reference for how to choose the appropriate dietary pattern in the future and for how to prevent bone loss caused by long-term poor dietary patterns in children, adolescents, and the elderly. In addition, this review provides dietary references for the clinical treatment of bone-related diseases and suggests that health policy makers should consider dietary measures to prevent and treat bone loss. [ABSTRACT FROM AUTHOR]