Quantization and diagnosis of Shanghuo (Heatiness) in Chinese medicine using a diagnostic scoring scheme and salivary biochemical parameters

Background: This study aims to establish a diagnostic scoring scheme for Shanghuo (Heatiness) and to evaluate whether Shanghuo is associated with biochemical parameters of salivary lysozyme (LYZ), salivary secreted immunoglobulin (S-IgA), salivary amylase (AMS), and saliva flow rate (SFR). Methods: We collected 121 Shanghuo patients at the Affiliated Hospitals of Guangzhou University of Traditional Chinese Medicine in Guangdong Province, 60 cases as a Shanghuo recovered group, and 60 healthy cases as a healthy control group. The diagnostic scoring scheme was established by probability theory and maximum likelihood discriminatory analysis on the basis of epidemiology with the design of self-controlled clinical trial. Subsequently, we used the same methods to collect 120 Shanghuo patients, 60 Shanghuo recovered cases, and 60 healthy cases in both Hunan Province and Henan Province. The levels of LYZ, S-IgA, AMS, and SFR were tested when the patients suffered from Shanghuo or recovered, respectively. Results: The diagnostic score table for Shanghuo syndrome was established first. In the retrospective tests, the sensitivity, specificity, accuracy, and positive likelihood ratio of the diagnostic score table were 98.9%, 93.5%, 97.5%, and 14.34%, respectively. In the prospective tests, the corresponding values were 94.9%, 85.7%, 91.7%, and 6.64%, respectively. Shanghuo was classified into three degrees based on the diagnostic scores, common Shanghuo: 63–120; serious Shanghuo: 121–150; very serious Shanghuo: >150. A negative correlation was found between Shanghuo and S-IgA (R = -0.428; P = 0.000). The level of S-IgA was also affected by seasonal and regional factors. No significant correlations were found between Shanghuo and the levels of LYZ, AMS, and SFR. Conclusions: In this study, Shanghuo could be diagnosed by the combination of the diagnostic score table and S-lgA level

Influence of axial spacing on stall development of FBCDZ-10-No20 mode contra-rotating fan

The rotating fan is prone to instability such as stall and even surge when operating at low flow rates. In order to study the influence of axial spacings on the stall inception and its development and propagation process of a contra-rotating fan , a Shear Stress Transport(SST) k-ω turbulence model was used to numerically simulate the unsteady flow in the whole passage of a FBCDZ-10-No20 contra-rotating fan. The stall evolution of fan under two axial spacings are investigated. The results show that the axial spacing has significant influence on the inception and development of fan stall.In the stall inception stage, when the axial spacing between the two-stage impellers is 170 mm, the stall inception first occurs within the rear impeller, which locates in the trailing edge area on the suction surface of the blade root. Then stall inception develops from the blade root to the tip area along the radial direction, and accumulates towards a blade passage along the circumferential direction and falls off on the way to form a blocking area, which eventually leads to stall. When the axial spacing is 70 mm, the stall inception successively occurs the tip area of the two-stage impellers. Then stall inception keeps increasing, which eventually leads to stall. During the full stall stage, the axial spacing has a significant effect on the propagation of the stall vortex in the circumferential, axial and radial directions. When the axial spacing is 170 mm, the type of stall vortex shows the single vortex full-blade high stall. The propagation range of the stall vortex in the axial direction is limited to the region of rear impeller, and rotates at 33.3% of the rear impeller speed in the circumferential direction; When the axial spacing is 70 mm, the type of stall vortex shows the multi-vortex partial blade high stall. The stall vortex are successively generated in the tip area of the two-stage impellers, propagating upward and downstream in the axial direction, and are dispersed in the area above 70% of the blade height of each blade channel in the radial direction. Due to the change of the axial distance between the two-stage impellers, the type of stall inception of the fan is changed from “partial surge type” to “Spike-type”

Effect of axial spacing on rotating stall performance of FBCDZ-10-No20 contra-rotating fan

Mining contra-rotating fan are prone to rotational stall when it operates at low flow rates, which seriously affects the operational stability. The unsteady flow in the full flow passage of a FBCDZ-10-No20 contra-rotating fan at five axial spacings was numerically simulated by using the SST k-ω turbulence model. The effect of axial spacing on the stall process of contra-rotating fan was studied, and the mechanism of stall inception and development at different axial spacings was revealed. The results shown that the axial spacing had a significant influence on the initial position, type and development of stall inception. For the axial spacings of 70 mm and 100 mm, the stall inception first occurred at the tip of the front stage, and subsequently appeared at the tip of the rear stage due to the rotor-rotor interaction between the two stages. However, compared with the axial spacing of 70 mm, the rotor-rotor interaction at the axial spacing of 100 mm was relatively weak, making it take longer for a stall inception to occur in the rear stage. For all three axial spacings of 140 mm, 170 mm and 225 mm, the stall inception occurred first in the root of rear stage. The difference was that for the axial spacing of 140 mm, the leakage flow at the tip of the front stage cannot completely flow out of the channel with the main flow, and a localized tip blockage area was formed. However, for both spacings of 170 mm and 225 mm, there was almost no blockage area at the tip of the front stage, and eventually only mature stall vortices formed in the rear stage. With the increase of the axial spacing, the blockage area formed by both the leading edge overflow and the trailing edge reverse flow those originated from the leakage flow at the tip of the front stage gradually reduced. In contrast, the blockage area formed by the radial vortex on the suction surface near the root of the rear stage gradually increased. When the leakage flow at the tip of the front stage failed to form blockage area, the stall type changed from the “spike type” induced by the tip leakage flow at the front stage to the “localized surge type” induced by the radial vortex flow at the root of the rear stage

Resting-state functional magnetic resonance imaging reveals brain remodeling after Tuina therapy in neuropathic pain model

Tuina, a method of traditional Chinese manual manipulation, is an effective alternative therapy for neuropathic pain (NP), but its analgesic mechanism remains unclear. In this study, we used resting-state functional magnetic resonance imaging (R-fMRI) to explore the analgesic mechanism of Tuina in an NP rat model. After undergoing surgery to induce chronic compression of the dorsal root ganglion (CCD), one group of rats underwent Tuina at the ipsilateral BL40 acupoint once a day for 10 min during the 25 days following surgery while another group did not. Behavioral tests were performed at baseline, on the third day following surgery, and once a week for the next 4 weeks. R-fMRI was performed at baseline and 7 days and 28 days following surgery. Behavioral testing revealed that the Tuina group presented a significant response improvement to mechanical and thermal nociception stimuli compared to the untreated group 2 weeks following CCD surgery. Interestingly, rats submitted to Tuina presented higher measures of spontaneous neuronal activity in basal forebrain region, primary somatosensory cortex barrel field, dentate gyrus, secondary somatosensory cortex, striatum, descending corticofugal pathways, and globus pallidum of the left hemisphere 4 weeks after the CCD surgery compared to rats having undergone CCD only. In addition, on the 28th day, the ALFF signals of the left dentate gyrus, left secondary somatosensory cortex, left striatum, and bilateral primary cingulate cortex were significantly increased while those in the right dentate gyrus and bilateral periaqueductal gray were significantly decreased compared to those on the 7th day. Correlation analysis showed that the ALFF values of the left descending corticofugal pathways and globus pallidum had a positive correlation with mechanical withdrawal threshold and paw withdrawal thermal latency tests. Altogether, these results indicate that NPP induced by CCD surgery affects the plasticity of the cerebral cortex, and that Tuina alleviate pain behavior by promoting cortical remodeling

Low-Cyclic Loading Tests of Self-Centering Variable Friction (SCVF) Brace

A novel assembled self-centering variable friction (SCVF) brace is proposed which is composed of an energy dissipation system, a self-centering system, and a set of force transmission devices. The hysteretic characteristics and energy dissipation of the SCVF brace with various parameters from low-cyclic loading tests are presented. A finite element model was constructed and tested under simulated examination for comparative analysis. The results indicate that the brace shows an atypical flag-type hysteresis curve. The SCVF brace showed its stable self-centering ability and dissipation energy capacity within the permitted axial deformation under different spring and friction plates. A larger deflection of the friction plate will make the variable friction of this SCVF brace more obvious. A higher friction coefficient will make the energy dissipation capacity of the SCVF brace stronger, but the actual friction coefficient will be lower than the design value after repeated cycles. The results of the fatigue tests showed that the energy dissipation system formed by the ceramic fiber friction blocks and the friction steel plates in the SCVF brace has a certain stability. The finite element simulation results are essentially consistent with the obtained test results, which is conducive to the use of finite element software for calculation and structural analysis in actual engineering design

Design of Aviation High Impedance Permanent Magnet Synchronous Generator

Permanent magnet generator is one of the key components of a three-stage electrically excited brushless synchronous motor, with a main function to provide excitation power for the main exciter and driving power for the controller. In order to improve the reliability and safety of the operation of the three-stage electrically excited brushless synchronous motor, the permanent magnet generator is required to provide sufficient power under all operating conditions and to have low short-circuit current when its own short-circuit fault occurs, so that the generator will not be burnt out due to overheating. Thus, power characteristic and high impedance characteristic are the key goals of designing a permanent magnet generator. In this paper, the fractional slot concentrated winding was adopted to calculate and analyze the electromagnetic properties of permanent magnet generators with different rotor structures, and the optimal design was obtained. A prototype was manufactured to conduct related experiments on the electromagnetic properties. The results demonstrated that the experimental data are basically consistent with the simulation data, and the permanent magnet generator can meet the design requirements for power and high impedance characteristics, with a high power density

Protective Effect of Ferulic Acid on Lipopolysaccharide-Induced BV2 Microglia Inflammation via AMPK/mTOR Signaling Pathway

In neurodegenerative diseases, microglial activation and neuroinflammation are essential for the control and progression of neurodegenerative diseases. Mitigating microglium-induced inflammation is one strategy for hindering the progression of neurodegenerative diseases. Ferulic acid (FA) is an effective anti-inflammatory agent, but its potential role and regulation mechanism in neuroinflammatory reactions have not been fully studied. In this study, the neuroinflammation model was established by lipopolysaccharide (LPS), and the inhibitory effect of FA on neuroinflammation of BV2 microglia was studied. The results showed that FA significantly reduced the production and expression of reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α), leukocyte-6 (IL-6) and interleukin-1β (IL-1β). We further studied the mechanism of FA’s regulation of LPS-induced BV2 neuroinflammation and found that FA can significantly reduce the expression of mTOR in BV2 microglia induced by LPS, and significantly increase the expression of AMPK, indicating that FA may have an anti-inflammatory effect by activating the AMPK/mTOR signaling pathway to regulate the release of inflammatory mediators (such as NLRP3, caspase-1 p20 and IL-1β). We further added an autophagy inhibitor (3-MA) and an AMPK inhibitor (compound C, CC) for reverse verification. The results showed that FA’s inhibitory effects on TNF-α, IL-6 and IL-1β and its regulatory effect on AMPK/mTOR were destroyed by 3-MA and CC, which further indicated that FA’s inhibitory effect on neuroinflammation is related to its activation of the AMPK/mTOR autophagy signaling pathway. In a word, our experimental results show that FA can inhibit LPS-induced neuroinflammation of BV2 microglia by activating the AMPK/mTOR signaling pathway, and FA may be a potential drug for treating neuroinflammatory diseases

Cerebral mechanism of Tuina analgesia in management of knee osteoarthritis using multimodal MRI: study protocol for a randomised controlled trial

Background The chronic pain of patients with knee osteoarthritis (KOA) seriously affects their quality of life and leads to heavy social and economic burden. As a nondrug therapy in Traditional Chinese Medicine (TCM), Tuina is generally recognised as safe and effective for reducing the chronic pain of KOA. However, the underlying central mechanisms of Tuina for improving the pain of KOA are not fully understood. Methods/design This study will be a randomised controlled trial with a parallel-group design. A total of 60 eligible participants will be assigned to the Tuina group or healthcare education group (Education group) at 1:1 ratio using stratified randomisation with gender and age as factors. The interventions of both groups will last for 30 min per session and be conducted twice each week for 12 weeks. This study will primarily focus on pain evaluation assessed by detecting the changes in brain grey matter (GM) structure, white matter (WM) structure, and the cerebral functional connectivity (FC) elicited by Tuina treatment, e.g., thalamus, hippocampus, anterior cingulate gyrus, S1, insula, and periaqueductal grey subregions (PAG). The two groups of patients will be evaluated by clinical assessments and multimodal magnetic resonance imaging (MRI) to observe the alterations in the GM, WM, and FC of participants at the baseline and the end of 6 and 12 weeks' treatment and still be evaluated by clinical assessments but not MRI for 48 weeks of follow-up. The visual analogue scale of current pain is the primary outcome. The Short-Form McGill Pain Questionnaire, Western Ontario and McMaster Universities Osteoarthritis Index, 36-Item Short Form Health Survey, Hamilton Depression Scale, and Hamilton Anxiety Scale will be used to evaluate the pain intensity, pain feeling, pain emotion, clinical symptoms, and quality of life, respectively. MRI assessments, clinical data evaluators, data managers, and statisticians will be blinded to the group allocation in the outcome evaluation procedure and data analysis to reduce the risk of bias. The repeated measures analysis of variance (2 groups x 6 time points ANOVA) will be used to analyse numerical variables of the clinical and neuroimaging data obtained in the study. PDiscussion The results of this randomised controlled trial with clinical assessments and multimodal MRI will help reveal the influence of Tuina treatment on the potential morphological changes in cortical and subcortical brain structures, the white matter integrity, and the functional activities and connectivity of brain regions of patients with KOA, which may provide scientific evidence for the clinical application of Tuina in the management of KOA. Dissemination The results will be published in peer-reviewed journals and disseminated through the study's website, and conferences