Identification of chemical constituents of Qingjin Yiqi granules and comparative study on pharmacokinetics of 23 main bioactive components in normal and Lung-Qi deficiency rats by UPLC-MS/MS method.

Qingjin Yiqi granules (QJYQ granules) are hospital preparations derived from ancient prescriptions under the guidance of academician Zhang Boli; they have the effect of invigorating qi and nourishing yin, strengthening the spleen and harmonizing the middle, clearing heat, and drying dampness, and are mainly used for patients with coronavirus disease 2019 (COVID-19) during the recovery period. However, their chemical constituents and pharmacokinetic characteristics in vivo have not been systematically investigated. In this study, 110 chemical constituents of QJYQ granules were identified using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), and a fast and sensitive ultra-high-performance liquid chromatography-mass spectrometry method was developed and validated for the target analytes. A rat model of lung-qi deficiency was established by subjecting mice to passive smoking combined with cold baths, and 23 main bioactive components of QJYQ granules were analyzed in normal and model rats after oral administration. The results showed that, compared to the normal group, there were significant differences in the pharmacokinetics of baicalin, schisandrin, ginsenoside Rb1, naringin, hesperidin, liquiritin, liquiritigenin, glycyrrhizic acid, and hastatoside in the model rats (P < 0.05), indicating that the in vivo processes of the above components changed under pathological conditions, suggesting that they may have pharmacological effects as active components. This study has helped identify QJYQ particulate substances and further supports their clinical application..

Error identification and compensation regarding the kinematic parameter of the MD-PEF for tibial deformity correction.

The correction accuracy of an external fixator is crucial to the treatment outcome of deformity correction and patient safety. In this study, the mapping model is established between the pose error and kinematic parameter error of the motor-driven parallel external fixator (MD-PEF). Subsequently, the kinematic parameter identification and error compensation algorithm of the external fixator is established based on the least squares method. An experimental platform based on the developed MD-PEF and Vicon motion capture system is constructed for kinematic calibration experiments. Experimental results show that the correction accuracy of the MD-PEF after calibration is as follows: translation accuracy dE1 = 0.36 mm, axial translation accuracy dE2 = 0.25 mm, angulation accuracy dE3 = 0.27°, and rotation accuracy dE4 = 0.2°. The accuracy detection experiment verifies the kinematic calibration results, which further validates the feasibility and reliability of the error identification and compensation algorithm constructed by the least squares method. The calibration approach used in this work also provides an effective way to improve the accuracy of other medical robots.

Established UPLC-MS/MS procedure for multicomponent quantitative analysis of rat plasma: Pharmacokinetics of Taohong Siwu Decoction in normal and acute blood stasis models.

ETHNOPHARMACOLOGICAL RELEVANCE: As one of China's 100 classic recipes, Taohong Siwu Decoction (THSWD) consists of Siwu Tang flavored peach kernel and safflower, and is used to nourish and activate blood. Accordingly, THSWD is mainly administered to treat blood deficiency and stasis syndrome. According to prior studies, THSWD induces antioxidant stress, inhibits inflammatory reactions, inhibits platelet aggregation, prevents fibrosis, reduces blood lipids, prolongs clotting time, prevents atherosclerosis and vascular pathology, improves hemorheological changes, and regulates related signaling pathways. MATERIALS AND METHODS: A sensitive analytical method was developed to detect the marker components of THSWD using UPLC-Q-TOF-MS. A rapid and sensitive UPLC-MS/MS analytical method was developed and applied to detect 16 major bioactive components in normal and acute blood stasis (ABS) rats following oral administration of THSWD. The metabolic process of THSWD in vivo was evaluated and the differences in pharmacokinetic parameters between the normal and ABS rat metabolic processes were compared. RESULTS: This method was fully validated based on its excellent linearity (r2 < 0.99), satisfactory intra- and inter-day precisions (RSD <15%), and good accuracy (RE within ±14.83%). The stability, matrix effects, and extraction recoveries of the rat plasma samples were also within the acceptable limits (RSD <15%). Compared to normal rats, the pharmacokinetics of the major active constituents (except Senkyunolide G) were significantly different (P < 0.05) in the ABS model rats, indicating that the metabolism of the 16 compounds in vivo may change under disease conditions. CONCLUSIONS: In this study, a sensitive UPLC-Q-TOF-MS method was established to analyze the main components of THSWD, and a UPLC-MS/MS analytical method was developed and applied for the pharmacokinetic parameter detection of the 16 main bioactive components in normal and ABS rats. Our findings lay the foundation for further studies on the pharmacokinetic-pharmacodynamic correlation for THSWD.

Multi-parameter influenced acquisition model with an in-orbit jitter for inter-satellite laser communication of the LCES system.

With the development of large low earth orbit (LEO) communication constellations, the efficiency of laser inter-satellite link (ISL) establishing become the bottleneck for subsequent large-scale launch and rapid networking applications of LEO communication constellations. Hence, we establish the pointing jitter error structure of LEO communication experiment satellites (LCES) system. The error structure can be used to trace the source of errors and evaluate the in-orbit jitter. And we derive an analytical expression of the acquisition probability density function (PDF) which comprehensively considering the influence of the scanning region, the pointing jitter error, the overlap factor and the in-orbit jitter error. The multi-parameter influenced acquisition model is validated by Monte Carlo (MC) simulations and semi-physical tests. The results reveals that the multi-parameter influenced acquisition model can be used to guide the in-orbit ISL establishing.

Optimal Progressive Pitch for OneWeb Constellation with Seamless Coverage.

Large-scale broadband low earth orbit (LEO) satellite systems have become a possibility due to decreased launch costs and rapidly evolving technology. Preventing huge LEO satellite constellations from interfering with the geostationary earth orbit (GSO) satellite system, progressive pitch is a technique to avoid interference with the GSO satellite system that allows the LEO satellite system to maintain a certain angle of separation from the GSO satellite system. Aside from interference avoidance, there is also a need to ensure seamless coverage of the LEO constellation and to optimize the overall transmission capacity of the LEO satellite as much as possible, making it extremely complex to design an effective progressive pitch plan. This paper models an inline interference event and seamless coverage and builds an optimization problem by maximizing transmission capacity. This paper reformulates the problem and designs a genetic algorithm to solve it. From the simulation results, the strategy can avoid harmful interference to the GSO satellite system and ensure the seamless coverage of the LEO constellation, and the satellite transmission capacity is also maximized.

An Interference Inspection Algorithm of Limb and Hexapod Frame in the Treatment of Lower Limb Deformity.

Pre-operative correction trajectory planning is one of the important aspects of deformity correction. Avoidance of limb-frame interference is essential to verify the implementability of the preplanned correction trajectory, as well as to maintain the continuity and security of the correction strategy. In this study, a novel interference inspection algorithm is developed to investigate the interaction of the limb and hexapod frame in the treatment of lower limb deformities. The algorithm is built on a minimum distance model of the cone frustum busbar and cylindrical axis using vector analysis. A predefined trajectory is generated by Cartesian coordinate path control. Subsequently, an interference case is performed through numerical simulation and motion simulation. The results show that the conclusion of numerical simulation and motion simulation is consistent, which prove the feasibility of the algorithm. The results also show that it is possible to identify the riskiest struts, which are prone to interfere with the limb, and the riskiest positions. The proposed algorithm can support the clinician in selecting the suitable frame configuration to avoid interference. The algorithm solves the problem that the interference can only be judged by clinical observation in the clinic.

A Method for Detecting Incipient Faults in Satellites Based on Dynamic Linear Discriminant Analysis.

Timely detection and treatment of possible incipient faults in satellites will effectively reduce the damage and harm they could cause. Although much work has been done concerning fault detection problems, the related questions about satellite incipient faults are little addressed. In this paper, a new satellite incipient fault detection method was proposed by combining the ideas of deviation in unsupervised fault detection methods and classification in supervised fault detection methods. First, the proposed method uses dynamic linear discriminant analysis (LDA) to find an optimal projection vector that separates the in-orbit data from the normal historical data as much as possible. Second, under the assumption that the parameters obey a multidimensional Gaussian distribution, it applies the normal historical data and the optimal projection vector to build a normal model. Finally, it employs the noncentral F-distribution to test whether a fault has occurred. The proposed method was validated using a numerical simulation case and a real satellite fault case. The results show that the method proposed in this paper is more effective at detecting incipient faults than traditional methods.

A Satellite Incipient Fault Detection Method Based on Decomposed Kullback-Leibler Divergence.

Detection of faults at the incipient stage is critical to improving the availability and continuity of satellite services. The application of a local optimum projection vector and the Kullback-Leibler (KL) divergence can improve the detection rate of incipient faults. However, this suffers from the problem of high time complexity. We propose decomposing the KL divergence in the original optimization model and applying the property of the generalized Rayleigh quotient to reduce time complexity. Additionally, we establish two distribution models for subfunctions F1(w) and F3(w) to detect the slight anomalous behavior of the mean and covariance. The effectiveness of the proposed method was verified through a numerical simulation case and a real satellite fault case. The results demonstrate the advantages of low computational complexity and high sensitivity to incipient faults.

Influence of parameter deviation on the closeness of the tibial limb and external fixator based on a novel collision detection algorithm.

The Ortho-SUV frame (OSF) is a hexapod external fixator widely applied in orthopedics deformity correction. The possibility of collision between OSF's struts and the soft tissue is an essential but overlooked issue. To avoid the issue, a novel collision detection algorithm is established based on a cone-cylinder model of the tibial limb-strut interaction for detecting the closeness of the tibial limb and external fixator. The algorithm is constructed using the vector analysis based on the model of the minimum distance between the truncated cone generatrix and the cylinder axis. The motion simulation is performed on the overall alignment through the Solidworks-motion module to verify the feasibility of the algorithm. Subsequently, the installation parameter deviations of the bone-fixator system are described to investigate the influence of orientation and position deviation on the closeness of the tibial limb and external fixator through the numerical method. The investigation results show that the orientation deviation γ (around the z-axis), the position deviation τ1 and τ2 (along the x and y-axes, respectively) have greater sensitivity to closeness and the influence of multiple deviations on the closeness has the property of superposition. The proposed algorithm can assist clinicians to strictly design and appraise frame configurations prior to their application to avoid the collision between the external fixator and the limbs during the correction. It has great application significance in the development of computer-aided correction software.

Comparison of three different correction trajectories for foot and ankle deformity treated by supramalleolar osteotomy using a novel external fixator.

Based on the principle of distraction osteogenesis, external fixators are widely used in deformity correction of the foot and ankle. In this study, a novel ankle external fixator is proposed to correct complex multiplane deformities, especially for supramalleolar osteotomy to correct distal tibia deformities. The relatively simple structure and fewer struts in the proposed fixator reduce the complexity of adjusting the external fixator. Based on two existing adjustment strategies, a new strategy taking into account the orientation and shortest path of the ankle joint center is proposed, which is named joint adjustment for equal bone distraction. By proposing the inverse kinematic solutions of the novel external fixator, mathematical derivations of the bone trajectory and modelling of the bone shape for the three distraction strategies are performed. The results obtained by comparative analysis indicate that a uniformly spaced path of the ankle joint center can be acquired, and a smooth and uniform correction trajectory of the distal tibia end can be obtained using the new adjustment strategy. It can avoid bone end interference and only generates a maximum deviation 0.66% greater than the currently optimal 1 mm/day. The new strategy can perform multiplane corrections simultaneously, which shortens the correction time and reduces the patient's pain.

Investigation of Correction Trajectory Considering Bone End-Plane Orientation and the Shortest Growth Path.

External fixators are widely used in orthopedics for the purposes of fracture reduction and bone deformity correction. Since there is nonlinear mapping between the joint and operation spaces of the external fixator, bone correction trajectories achieved by equally adjusting the length of the struts in the joint space are usually not the trajectories that clinicians expect. Based on two different adjustment strategies, a new strategy considering bone end-plane orientation and the shortest growth path is proposed to plan the position and orientation of the distal bone end, which is named joint adjustment for equal bone distraction. By proposing the inverse and forward kinematic solutions of an Ortho-SUV external fixator, correction trajectories with three different adjustment strategies are generated and compared, and the bone shapes for each strategy are modeled. The results obtained by comparative analysis indicate that a smooth and uniformly spaced linear trajectory can be acquired using the new adjustment strategy, which can avoid bone end interference and maintain an optimal distraction rate of 1.03 mm/day, with only a 3% error compared with 1 mm/day. The new strategy can perform multiplane corrections simultaneously and is beneficial for stimulating the growth of new bone tissue.