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The spin state of M–N4 single-atom catalysts was found to impact their catalytic properties for oxygen reduction reactions.

This study investigated the effect of salvia miltiorrhiza-asarum ointment (SMAO) plus Chinese medical massage on knee osteoarthritis in a rat model.Hulth's method was used to establish a Sprague-Dawley rat model of knee osteoarthritis (OA). The levels of matrix metalloproteinase-13 (MMP-13), collagen-II, aggrecan, interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), and IL-6 were measured by enzyme-linked immunosorbent assays. The joint space was assessed by a Perlove X-ray system. Histopathology was examined by hematoxylin-eosin and Safranin O staining. The mRNA and protein expression levels of Notch1, MMP-13, collagen-II, and aggrecan were measured by quantitative reverse transcription-polymerase chain reaction and Western blotting, respectively.SMAO plus Chinese medical massage significantly decreased the levels of MMP-13, IL-1β, TNF-α, and IL-6, and increased serum collagen-II and aggrecan levels. Pathological injury of the knee joint was improved by SMAO treatment. mRNA and protein expression of Notch1 and MMP-13 was remarkably downregulated, but collagen-II and aggrecan levels were significantly upregulated in cartilage tissues.SMAO combined with Chinese medical massage effectively relieves OA symptoms, which may involve inhibiting inflammation through the Notch1/MMP-13 signaling pathway.

Objective Intrathecal dexmedetomidine has been used in spinal anesthesia during cesarean sections. The purpose of this meta-analysis was to investigate the effect of intrathecal dexmedetomidine on the adverse reactions of spinal anesthesia during cesarean section. Methods We searched for relevant studies using PubMed, Web of Science, and the Cochrane library. After screening studies and extracting data, we performed a meta-analysis on the effect of intrathecal dexmedetomidine during cesarean section. Results A total of 278 patients from 4 studies were included in this meta-analysis. The incidence of shivering in the dexmedetomidine groups was significantly lower than that in the placebo groups during cesarean section (RR=0.40, 95% CI [0.25, 0.65], P=0.0002). Intrathecal dexmedetomidine had no effect on nausea and vomiting (RR=1.08, 95% CI [0.68, 1.71], P=0.74), bradycardia (RR=1.33, 95% CI [0.31, 5.76], P=0.70), and hypotension during cesarean section (RR=0.78, 95% CI [0.59, 1.03], P=0.08). Conclusion Intrathecal dexmedetomidine can effectively reduce the occurrence of shivering during cesarean section, but it does not affect the occurrence of nausea and vomiting, bradycardia or hypotension.

Objective: To investigate the effects of general anesthesia combined with epidural anesthesia on stress response, inflammation level and coagulation function in patients undergoing laparoscopic colon cancer resection during intraoperative and postoperative. Methods: A total of 98 patients undergoing colon cancer radical surgery in our hospital from August 2015 to August 2017 were randomly divided into control group and observation group with 49 cases in each group. In the control group, systemic intravenous anesthesia was used; and in the observation group, a systemic intravenous anesthesia combined epidural anesthesia was used. Serum of venous blood was collected from patients before anaesthesia, 30 min after anesthesia, and two hours after operation to detect stress response indexes, such as adreno-cortico-tropichormone (ACTH), adrenaline (AD), norepinephrine (NE) and cortisol (Cor), and inflammatory response indexes, such as tumor necrosis factor-α (TNF-α), procalcitonin (PCT) and C-reaction protein (CRP). Venous blood was collected at the same time points for coagulation testing. Functional indicators such as prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and fibrinogen (FBG) were detected. Results: There was no significant difference in the level of each index between the two groups before anesthesia. At 30 minutes after anesthesia and at 2 hours after operation, the stress response indicators and inflammatory response indicators in the observation group were lower than those in the control group at the same time points; apart of the blood coagulation function indexes (PT, APTT and TT) in the observation group were higher than the corresponding indicators of the control group at the same time points, but the FBG content in the observation group was lower than that of the control group at the same time points, and these differences were significant. Conclusion: The method of general anesthesia combined with epidural anesthesia can effectively reduce the stress and inflammatory reaction during and after operation of laparoscopic colon cancer resection, and reduce the abnormal coagulation function as well as the blood hypercoagulability.

In TAKR 300 (Bob Hope) Class transport ships, the builder observed cracking of steel cloverleaf vehicle tie-down deck sockets following installation. Sockets were made from AH36 steel plate by flame cutting and cold coining, then submerged-arc welded to the shop deck. Cracks initiated from the tip of the cloverleaf pattern in >300 cases aboard several cargo vessels in various stages of construction. Consultants who analyzed the situation concluded that the problem may have been corrosion and hydrogen embrittlement. Three possible mechanisms of failure were considered: overload failure; fatigue fracture; and, environmentally-assisted cracking. Testing indicated overload failure was the cause. Remedial actions were taken to improve the fracture properties of the deck socket. A modified manufacturing process was developed involving milling and cutting instead of coining to round the comers of the flame-cut cloverleaf lobe. This new manufacturing process solved the problem.

Objective Intrathecal dexmedetomidine has been used in spinal anesthesia during cesarean sections. The purpose of this meta-analysis was to investigate the effect of intrathecal dexmedetomidine on the adverse reactions of spinal anesthesia during cesarean section. Methods We searched for relevant studies using PubMed, Web of Science, and the Cochrane library. After screening studies and extracting data, we performed a meta-analysis on the effect of intrathecal dexmedetomidine during cesarean section. Results A total of 278 patients from 4 studies were included in this meta-analysis. The incidence of shivering in the dexmedetomidine groups was significantly lower than that in the placebo groups during cesarean section (RR=0.40, 95% CI [0.25, 0.65], P=0.0002). Intrathecal dexmedetomidine had no effect on nausea and vomiting (RR=1.08, 95% CI [0.68, 1.71], P=0.74), bradycardia (RR=1.33, 95% CI [0.31, 5.76], P=0.70), and hypotension during cesarean section (RR=0.78, 95% CI [0.59, 1.03], P=0.08). Conclusion Intrathecal dexmedetomidine can effectively reduce the occurrence of shivering during cesarean section, but it does not affect the occurrence of nausea and vomiting, bradycardia or hypotension.

Spray forming is a new developed advanced metal-forming process, of which the property benefits from rapid solidification. The porosity produced during the atomization progress can obviously decrease the material performance. In this paper, a self-designed Laval-type atomizer is used to improve atomization efficiency. The atomization results show that the atomizer can obtain well atomization effect at a relative lower atomization pressure, and the mass median diameter d50 is 63.5μm and 43.4μm when the atomization gas pressure P0=0.4 and 0.8MPa separately. The technological parameters are optimized by overall considering the atomized droplet size, gas consumption, deposition property, and the metal yield. By the designed atomizer, the as-deposited billet with lower porosity content can be obtained with the technological parameters of the melting temperature T=800°C, atomization pressure P0=0.6MPa, and spray distance h=500mm. Further test with the deposited billet show that the grain size of the spray formed 7055-Al alloy is mainly ranging 10~30μm, which is about one third of that of as-cast billet.

The non-linear relationship between the magnetic field intensity and magnetostrictive strain which is caused by the thermal expansion produced by the eddy current loss in the GMM rod, will affect the precision and stability of GMM actuator. This paper tries to reduce the eddy current loss in the GMM rod to improve the performance of magnetostrictive actuator by machining radial grooves in the surface of the rod. The numerical results show that the axial grooves can be effective in reducing thermal power loss. The groove size and number are both optimized by numerical method. The results show that the groove depth and number has great impact on the unit volume eddy current loss while the groove width has little or no impact. The test of the magnetostrictive strain shows that the linearity of the GMM rod with grooves is significantly improved. The radial grooves in the GMM surface can reduce the eddy current loss and improve the performance of GMM actuator.

For aircraft sheet metal parts digital cutting, this paper uses IDEF0 to structure a digital system integrated with unfolding module, nesting module, cutting path planning module and NC cutting module, then analyzes data organization and process of the system application. In the system, an algorithm for the development of a doubly curved surface onto a plane is adopted, NC cutting process-oriented nesting algorithm is presented and rules of cutter path planning is developed. Furthermore, application examples of key technologies (unfolding, nesting, path cutter planning) are demonstrated and indicate that the system can realize digital cutting for aircraft sheet metal parts quickly and precisely.

The function model of digital manufacturing system of aircraft wing integral panel is proposed using IDEF0. The digital integral panel manufacturing subsystems including process design, manufacturing model definition, tooling design and manufacturing, process information management, fabrication and inspection are described. In this system, the integral panel is formed by shot peen forming process, and the corresponding approach to solve some key manufacturing problems is described. The part manufacturing model is presented to represent the intermediate part in the fabrication process. The information flow model of the system is built. The application of the system into engineering is analyzed, and it is shown that digital manufacturing of wing integral panel can shorten the cycle, lower the cost and improve quality.

Objective To investigate the nature of the restoration of cell polarity and bile excretion function in Sandwich-cultured hepatocytes. Methods Freshly isolated hepatocytes from male Sprague-Dawley rats were cultured in a double layer collagen gel Sandwich configuration. Morphological changes were observed under a inverted microscope. The domain specific membrane associated protein DPP IV was tested by immunofluorescence. and the bile excretion function was determined by using fluorescein diacetate. Hepatocytes cultured on a single layer of collagen gel were taken as control. Results Adult rat hepatocytes cultured in a double layer collagen gel sandwich configuration regained its morphological and functional polarity and maintained polygonal morphology for at least 4 weeks. Immunofluorescence studies using antibodies against DPP IV showed polarity restoration as early as 48 h. After cultured in the double layer collagen gel Sandwich configuration for 96 h the hepatocytes began to excrete bile; while hepatocytes cultured on a single layer collagen gel had no bile excretion. Conclusion Hepatocytes cultured in a double layer collagen gel Sandwich configuration are able to regain their morphological and functional polarity given certain conditions. Hepaotcyte culture is a useful tool for the study of polarity restoration.

In this paper, algorithms are presented for predicting peen forming parameters of integral aircraft wing panels with complex airfoil shapes. The peen forming deformation is divided into stretching deformation and bending deformation. The stretching deformation is assumed to result from the tensile strain within the plane panel, and the bending deformation corresponds to the difference of maximum and minimum curvature of the airfoil surface. The distribution of the forming tensile strain within the panel is obtained by optimal mapping of the airfoil surface in the sense that the stretching deformation energy from the plane panel to its spatial shape is minimized. In order to fit the nonlinear relation between the peening parameters and the deforming parameters, a back-propagation (BP) artificial neural network (ANN) is modeled with input parameters of thickness, curvature, tensile strain, etc, to predict the peening parameters of coverage, air pressure and intensity. Experimental peen forming data are given to train the BP ANN. It’s verified that the predicting methods are effective.

To develop a novel culture system to investigate the effects of ethanol on the function of cultured hepatocytes.Sandwich configuration was used to culture hepatocytes and the effects of ethanol on functions of bile excretion and protein synthesis as well as the morphology of cultured hepatocytes were observed.Bile canaliculi-like structures decreased and anastomatic networks disappeared in ethanol treated hepatocytes. The ability for hepatocytes to internalize, metabolize and excrete compounds into bile was indicated by FDA metabolizing in the hepatocytes. In hepatocytes without ethanol, the bile excretion was showed clearly, but in ethanol-interfered hepatocytes, no bile excretion was observed. After ethanol was given, the level of protein secretion decreased and with the time going, it became lower and lower.Hepatocytes can be seriously damaged by ethanol. The study provides a new model to investigate the mechanism of some liver diseases caused by ethanol.