The serum urea nitrogen, creatinine, and high-sensitivity C-reactive protein (hs-CRP) in non-survivors was significantly elevated in comparison with survivors (16.54 ± 2.45 vs 2.87 ± 0.58, p < 0.001; ...184.68 ± 41.27 vs 63.42 ± 6.21, p < 0.001; 217.47 ± 46.35 vs 27.65 ± 21.83, p = 0.002, respectively). ...at a later stage (second peak wave), the hs-CRP level continued to increase and peaked on the 7th day, which suggested a stronger inflammatory immune response, while these individuals also exhibited multiple organ dysfunction 4. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a Retrospective Cohort Study.
Traditional intelligent fault diagnosis methods focus on distinguishing different fault modes, but ignore the deterioration of fault severity. This paper proposes a new two-stage hierarchical ...convolutional neural network for fault diagnosis of rotating machinery bearings. The failure mode and failure severity are modeled as a hierarchical structure. First, the original vibration signal is transformed into an energy spectrum matrix containing fault-related information through wavelet packet decomposition. Secondly, in the model training method, an adaptive learning rate dynamic adjustment strategy is further proposed, which adaptively extracts robust features from the spectrum matrix for fault mode and severity diagnosis. To verify the effectiveness of the method, the bearing fault data was collected using a rotating machine test bench. On this basis, the diagnostic accuracy, convergence performance and robustness of the model under different signal-to-noise ratios and variable load environments are evaluated, and the feature learning ability of the method is verified by visual analysis. Experimental results show that this method has achieved satisfactory results in both fault pattern recognition and fault severity evaluation, and is superior to other machine learning and deep learning methods.
A kinematic equation of profiling float is nonlinear and has time-varying parameters. Traditional PD controllers not only demonstrate an inconsistent response to different depth controls but also ...face problems of overshooting and high power consumption. To realize the goal of depth control of profiling buoy under low power consumption, an improved double PD control method was proposed in this paper. The real-time prediction of position and low-power running of the sensor were realized through sparse sampling and depth prediction. The combination control over position, speed, and flow was realized by introducing the speed and flow expectation function. Then, a MATLAB/Simulink simulation model was constructed, and the proposed controller was compared with a single PD controller and an improved single PD controller. Among ten depth control tests, the proposed method was superior given its short response time, small overshooting, small steady-state error, and low power consumption. Moreover, it achieved a consistent control effect on different target depths. The simulation results demonstrated that a nonlinear and time-varying floating system controlled by the proposed method has favorable robustness and stability. This system will consume minimal power simultaneously.
Abstract Aiming at the limitations of the existing hydraulic pumps, a new type of bidirectional water-hydraulic internal ball gear pump using concave-convex ball teeth meshing to transfer power is ...proposed. In this paper, the principle of internal gear pump is utilized to establish the model of internal ball gear pump, and its mechanical properties and dynamic meshing characteristics are numerically investigated by using the finite element method. The results show that (a) the concave-convex ball gears run smoothly without any interference, and (b) increasing the number of gear rows can effectively reduce the maximum stress and meshing impact under a given load and speed. This study provides a basis for the development of high-performance ball gear pumps.
Abstract As an advanced technology, digital-twin (DT) is an effective method to achieve information fusion and has been widely applied in fault diagnosis (FD). An integrated model, which consists of ...the DT model, consistency model, and FD network, is developed to detect faults in hydraulic systems (HS) by the dual effective information communication between the virtual model and real system. The consistency between the model and the real system can be guaranteed with the consistency model. A large number of labeled datasets generated by the DT model are used to train the FD network, which results in a significant reduction in the uncertainty of model parameters. A case study is done to investigate the performance of the DT method and the results show that the method can diagnose faults of HS effectively, efficiently, and accurately.
HuoXueTongFu Formula (HXTF) is a traditional Chinese herbal formula that has been used as a supplement and alternative therapy for intraperitoneal adhesion (IA). However, its specific mechanism of ...action has not been fully understood.
In surgery, IA presents an inevitable challenge, significantly impacting patients' physical and mental well-being and increasing the financial burden. Our previous research has confirmed the preventive effects of HXTF on IA formation. However, the precise mechanism of its action still needs to be understood.
In this study, the IA model was successfully established by using the Ischemic buttons and treated with HXTF for one week with or without Mer Tyrosine Kinase (MerTK) inhibitor. We evaluated the pharmacodynamic effect of HXTF on IA mice. The MerTK/phosphoinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway-associated proteins were detected by Western blotting. Neutrophil extracellular traps (NETs) were detected by immunofluorescence. Macrophage phenotype was assessed by immunohistochemistry and flow cytometry. Inflammatory cytokines were detected by Real Time Quantitative PCR and Western blotting.
HXTF reduced inflammatory response and alleviated IA. HXTF significantly enhanced MerTK expression, increased the number of M2c macrophages, and decreased the formation of NETs. In addition, the MerTK/PI3K/AKT pathway was significantly activated by HXTF. However, after using MerTK inhibitors, the role of HXTF in inducing M2c macrophage through activation of the PI3K/AKT pathway was suppressed and there was no inhibitory effect on NETs formation and inflammatory responses, resulting in diminished inhibition of adhesion.
HXTF may improve IA by activating the MerTK/PI3K/AKT pathway to induce M2c polarization, which removes excess NETs and attenuates the inflammatory response.
The caption of the abstract graphic: The HXTF improves IA by modulating the MerTK/PI3K/AKT pathway to induce M2c macrophages, increase phagocytosis of excess NETs, and reduce inflammation. Display omitted
•HuoXueTongFu Formula (HXTF) ameliorated intraperitoneal adhesion (IA) in Mice.•HXTF induced M2c macrophage and removed excessive NETs.•HXTF regulated the MerTK/PI3K/AKT pathway to induce M2c macrophage and was verified by using MerTK inhibitor.
Abstract
Power control hydraulics (PCH) has one of the most versatile research fields and technologies that has many applications especially in the mechatronic industries. It also comes with ...drawbacks especially with issues concerning the use of mineral oil as a pressurized fluid in most of it applications. Furthermore, in the mechatronic field, researches in the ocean environment has become more difficult due to mineral oil incompatibility with the ocean water. One of the most accepted solution is to find alternatives to mineral oil as a PCH pressurized fluid which has led to water being the safest candidate. As a result, more researches have been carried out on water as a pressurized fluid in PCH systems. Axial hydraulic piston pump has been one of the best pumps for PCH systems. It was realized in this paper that, more options for material selection for the friction pairs were available and therefore water hydraulics can realize its main goals of providing a safe environment as well as being cost-effective. This paper seeks to review the various material friction pair selection that has been suggested by various researchers in this field and analyze their various methodologies and experimentations.
In order to improve the compactness and integration of electro-hydrostatic equipment to meet their miniaturization, a new electro-hydrostatic actuator (EHA) scheme is proposed, and the working ...principle and feature are introduced. The physical model of EHA is developed, numerical studies have been done to investigate the static and dynamic performances including the output force-pressure characteristics, the output speed-flow rate relationship, the load capacity and the dynamic response. The results show that: (1) the output force of the actuator is proportional to the working pressure and the output speed is proportional to the flow rate. (2) the EHA has a better load capacity, and the maximum output force is around 3720 N. (3) under a rated load of 3000N, the EHA has good dynamic performances with a rise time of 0.056s, an overshoot of 1.63% and a transient time of 0.17s. (4) the EHA can respond quickly and realize precise positioning. (5) the response time is related to the load, the pump displacement and the actuator effective area. The research results provide a theoretical basis for the development of high power density and efficient EHAs.
The ocean, which covers about 70% of the earth surface, contains abundant natural resources, such as organisms, minerals, energy resources, and etc. Development and utilization of ocean resources is ...an important way to solve the problems of population, resources and environment that human beings are confronting with. Besides, the underwater operation equipment plays an important role in the development and utilization of the ocean. The rotary dynamic seal, which exerts great effects on the static and dynamic performances, reliability, life span and etc. is a key technology of the underwater rotating equipment. This research focuses on the frictional properties of rotary dynamic Glyd-ring under water lubrication. A physical model is proposed to study the effects of rotational speed and working pressure on the maximum Von Mises stress numerically. A rotary seal test bench is developed and experiments have been carried out to investigate the friction, torque of Glyd-ring under different rotational speed, different sealing pressures on one or both seal sides. The research results provide a basis for the design of dynamic seals for deep sea equipment.
The East China coastal plain is one of the most important Neolithic culture areas in China, where rich archaeological sites including those producing the earliest domesticated rice are observed. It ...is also a place where landscape has experienced dramatic evolution during the Holocene when both sea level and climate changed, such that it is an ideal place for studying human-environment interaction. This study investigated over 2000 sites of pre-history and Shang and Zhou Dynasties, with 655 of which being Neolithic ages, by using DEM and GIS methods. The results suggest that the spatial and temporal distribution of Neolithic sites has largely been controlled by landscape evolution （particularly changes in coastal line）, which ultimately governed by sea level changes. During early Holocene, Neolithic sites sparsely distributed in the intermountain basins of east Zhejiang Province, far from the influence of ocean. Over the period of 9-7 ka, the coastal plain （including the shelf） was largely submerged, only the feet of low hills to the south and southwest of the study area, and islands protruding the estuary, cradled limited number of settlements with characteristic ＂maritime components＂. At about 7 ka, sea level rise decelerated prominently, while sediments supply in the drainage remained high value, the combination of which led to land formation and propagation. Vast space during this period facilitated the growth of settlements in both size and number. In the mean time, however, the coastal plain was vulnerable to extreme environmental events such as storms and flooding owning to its geomorphic nature, which exerted great influence on the rise and fall of Neolithic culture.
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