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A high-precision testing bench is required for accurately assessing the dynamic Transmission error (TE) of precision reducers. However, the relationship between the testing bench's accuracy and deviations in testing conditions has not been determined, leading to an inaccurate evaluation of its metrological performance. In this study, we examined the accuracy characteristics of the testing bench. We analyzed the structure of the bench and identified the main error sources that affect its accuracy, including mechanical system deviation, sensor measurement deviation, and testing condition deviation. In addition, we studied the mechanism of these error sources and proposed a method to convert drive speed deviation and load torque deviation into angle deviation by using a three-dimensional characterization model of lost motion. Based on the expression of TE, we proposed an evaluation method for the accuracy of the testing bench. Furthermore, we presented the methods for calculating the error sources and proposed a method for determining the TE of adjacent units based on the specific coupling structure. Finally, we conducted practical tests to validate the effectiveness of the proposed method in evaluating the accuracy characteristics of the testing bench. We found that the relative test error between quasi-static TE and dynamic TE is small, and more accurate test results are obtained when applying an appropriate load. [ABSTRACT FROM AUTHOR]

Objective: Elderly patients with hip fractures are at a greater risk of developing postoperative delirium (POD), which significantly impacts their recovery and overall quality of life. Neuroinflammation is a pathogenic mechanism of POD. Taohong Siwu Decoction (THSWD), known for its ability to promote blood circulation and remove blood stasis, can effectively reduce inflammation in the nervous system. Therefore, the objective of this article is to provide a comprehensive summary of the clinical efficacy of THSWD in the prevention of POD. Additionally, it aims to investigate the underlying mechanism of THSWD in the prevention and treatment of POD using network pharmacology and molecular docking. Methods: We conducted a retrospective analysis of patients with intertrochanteric fractures between January 2016 and October 2021. The patients were divided into two groups: the control and THSWD group. We performed a comparative analysis of hemoglobin (HB), albumin (ALB), C-reactive protein (CRP), blood urea nitrogen (BUN), and the blood urea nitrogen to creatinine ratio (BCR) on two different time points: the day before surgery (D0) and the third day after surgery (D3). Furthermore, we examined the incidence and duration of delirium, as well as the Harris Hip Score (HHS) at 3 months and 12 months post-surgery. Network pharmacology was employed to identify the primary targets and mechanisms of THSWD in the management of delirium. Molecular docking was employed to confirm the interaction between active ingredients and COX-2. Inflammatory cytokines, including cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor- (TNF-α), were measured using the enzyme-linked immunosorbent assay (ELISA). The cognitive status of the patients was assessed using the Mini-Mental State Examination (MMSE) scoring system. Results: Regardless of whether it is in D0 or D3, THSWD treatment can increase HB levels while decreasing BCR. In D3, the THSWD group demonstrated a significant reduction in the expression of CRP and BUN when compared to the control group. However, there were no significant differences in ABL levels, surgery duration, and blood loss between the two groups. Additionally, THSWD treatment requires fewer blood transfusions and can reduce the incidence and duration of POD. The results of the logistic analysis suggest that both CRP levels and BCR independently contribute to the risk of POD. Network pharmacology analysis indicates that THSWD has the potential to prevent and treat POD possibly through inflammatory pathways such as IL-17 signaling pathways and NF-kappa B signaling pathways. Molecular docking validated the interaction between the active ingredient of THSWD and COX-2. Furthermore, THSWD treatment can reduce the levels of COX-2, IL-1β, IL-6, TNF-α, BUN and CRP in the blood of patients with POD, increase HB levels, and enhance MMSE scores. The expression of COX-2 is positively associated with other inflammatory markers (IL-1β, IL-6, TNF-α, and CRP), and inversely associated with MMSE. Conclusion: THSWD has been found to have a preventive and therapeutic effect on POD in intertrochanteric fracture patients possibly through inflammatory pathways. This effect may be attributed to its ability to increase hemoglobin levels and reduce the levels of certain detrimental factors, such as blood urea nitrogen and inflammatory factors. [ABSTRACT FROM AUTHOR]

With the widespread attention on hydrogen energy, the operation optimization of the coupling system of hydrogen energy and transportation has become a critical issue. Therefore, this study develops a hydrogen-containing energy transportation coupling system for the system collaborative operation framework, operation mode and equipment modelling of the system. Furthermore, a medium- to long-term operation optimization model and a short-term operation optimization model were constructed considering the differences in the operation of coupled systems at different timescales and operating costs as the objective function and power balance and system equipment as constraints. In the medium- and long-term operation optimization model, the planning scenario reduction method is used to reduce the wind power generation scenario. In the short-term operation optimization model, a multivariate uncertainty model is constructed to represent the uncertainty in the coupling system. Subsequently, the solution method of the model is proposed. Finally, a coupled system is simulated to verify the effectiveness of the model. (i) When the initial scene set is 600, the typical scene reduction method using Latin hypercube sampling and the Wasserstein distance can reduce operating costs by 7.60% and 9.49% compared with K-means reduction and K-media reduction methods. (ii) The sensitivity coefficients of hydrogen sales price, electricity sales price and maintenance rate to operating costs are –0.031%, –1.009% and 0.0105%, respectively. (iii) Considering multiple uncertainties can help make optimal decisions based on the overall consideration of disadvantage scenarios, thereby reducing system operating costs. [ABSTRACT FROM AUTHOR]

Lost motion is utilized to characterize the transmission accuracy of gear reducers and is commonly evaluated through the hysteresis curve method. In examinations of lost motion for large and medium-sized reducers, the default practice is the application of the equal torque gradient loading method. Nonetheless, for small-sized reducers, this approach is deemed inappropriate due to the constraints of the servo motor loading resolution. This study reveals that employing a larger unit torque for equal torque gradient loading can modify the shape of the hysteresis curve and influence the assessment of lost motion. As a result, this paper introduces two innovative loading techniques, namely equal position gradient loading and uniform speed loading, to address the limitations of equal torque gradient loading and reduce the demands on testing equipment. Subsequent experiments validate the issues associated with equal torque gradient loading, confirm the effectiveness of the two new loading techniques, and yield more comprehensive hysteresis curves. It is important to note that all three loading methods are influenced by the loading rate, but the two novel methods can mitigate the effects of loading rate dependency. [ABSTRACT FROM AUTHOR]

Objective: Unilateral biportal endoscopic (UBE) surgery has recently been used as a minimally invasive procedure for the treatment of lumbar spinal stenosis and is associated with less perioperative blood loss. However, perioperative hidden blood loss (HBL) may be neglected during UBE. This study aimed to examine the volume of HBL and discuss the influential risk factors for HBL during unilateral biportal endoscopic surgery. Methods: From January 2022 to August 2022, 51 patients underwent percutaneous unilateral biportal endoscopic surgery for lumbar spinal stenosis at the Department of Spinal Surgery of the Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University and were enrolled in this study. The data included general indicators (age, sex and body mass index [BMI]), underlying disease (hypertension and diabetes), laboratory test results (prothrombin time [PT], activated partial thromboplastin time [APTT], fibrinogen [Fbg]), and preoperative and postoperative hematocrit and hemoglobin), related imaging parameters (severity of intervertebral disc [IVD] degeneration and soft tissue thickness of the interlaminar approach), number of operated vertebrae and operation time. Total blood loss (TBL) and HBL during surgical procedures were measured via the Gross formula. Influential factors were further analyzed by multivariate linear regression analysis and t‐tests. Results: The mean HBL was 257.89 ± 190.66 mL for single‐operation patients and 296.58 ± 269.75 mL for two‐operation patients. Patients with lower PT (p = 0.044), deeper tissue thickness (p = 0.047), and diabetes mellitus were determined to have more HBL during UBE. The operation time might also be an important factor (p = 0.047). However, sex (p = 0.265), age (p = 0.771/0.624), BMI (p = 0.655/0.664), APTT (p = 0.545/0.751), degree of degenerated IVD (p = 0.932/0.477), and hypertension (p = 0.356/0.896) were not related to HBL. Conclusion: This study determined the different influential factors of HBL during UBE. PT, tissue thickness, and diabetes mellitus are the independent risk factors that affect HBL incidence. Long PT may decrease the volume of HBL within a certain range. Tissue thickness and diabetes mellitus can lead to an increased volume of HBL. [ABSTRACT FROM AUTHOR]

The hydrogenation of carbon dioxide (CO2) to produce light olefins is one of the most promising ways to utilize CO2 in power plant flue gas. However, the low concentration of CO2 (~10%) and the existence of water steam in the flue gas pose great challenges for the catalyst design. To address these problems, we introduced a Mg promoter and hydrophobic component into the Fe-based catalyst to improve the CO2 adsorption capacity and weaken the negative effects of water. The yield of light olefins on an optimized multifunctional Fe-based catalyst increased by 37% in low-concentration CO2 hydrogenation with water steam. A variety of characterizations proved that the Mg promoter played critical roles in regulating the adsorption capacity of CO2, increasing the surface electron density of Fe species, and promoting the formation of iron carbide active sites. The hydrophobic component mainly contributed to constraining the oxidation of iron carbides via water steam. It benefited from the rational design of the catalyst, showing how our multifunctional Fe-based catalyst has great potential for practical application in CO2 utilization. [ABSTRACT FROM AUTHOR]

Delayed wound healing is a public issue that imposes a significant burden on both society and the patients themselves. To date, although numerous methods have been developed to accelerate the speed of wound closure, the therapeutic effects are partially limited due to the complex procedures, high costs, potential side effects, and ethical concerns. While some studies have reported that the in-vivo application of Human Parathyroid Hormone (1–34) (hPTH(1–34)) promotes the wound-healing process, the definitive role and underlying mechanisms through which it regulates the behavior of fibroblasts and keratinocytes remains unclear. Herein, hPTH(1–34)'s role in cell migration is evaluated with a series of in-vitro and in-vivo studies, whereby hPTH(1–34)'s underlying mechanism in activating the two types of cells was detected. The in-vitro study revealed that hPTH(1–34) enhanced the migration of both fibroblasts and HaCaT cells. Ras-associated C3 botulinum toxin subunit 1 (Rac1), a classical member of the Rho family, was upregulated in hPTH(1–34)-treated fibroblasts and HaCaT cells. Further study by silencing the expression of Rac1 with siRNA reversed the hPTH(1–34)-enhanced cell migration, thus confirming that Rac1 was involved in hPTH(1–34)-induced cell behavior. In-vivo study on rat wound models confirmed the effects of hPTH(1–34) on fibroblasts and keratinocytes, with increased collagen deposition, fibroblasts accumulation, and Rac1 expression in the hPTH(1–34)-treated wounds. In summary, the present study demonstrated that hPTH(1–34) accelerated wound healing through enhancing the migration of cells through the up-regulation of Rac1 expression. [ABSTRACT FROM AUTHOR]