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Screw fasteners are undoubtedly one of the most important machine elements due to their outstanding characteristic to provide a high clamping force just with a simplified design. However, the loosen vibration is their inherent and inevitable fault. The friction locking approach is one of the basic locking fastener categories by enhancing the bearing load on the contact surface of thread by applying a locking force on an antiloosening nut. This locking force may cause more severe deformation in the nut. The contact stress distribution on the nut would be changed and that can cause the variation of the friction torque for the bolt joint. However, there exists no established design calculation procedure that accounts for the rotation deformation and its stiffness of the antiloosening nut under the locking force. The main objective of the work is to develop an analytical solution to the rotation deformation problem encountered in the antiloosening nut. The proposed model is supported by comparison with numerical finite element analysis of different sizes of joint elements and different applied forces.

The aim of this article is to provide some basis for the design and assembly of a bolted rotor with curvic couplings. It is well known that the key difference between a bolted rotor with curvic couplings and an integrated one is the contact interface. According to the characteristics of curvic couplings and spindle bolts, the model of a bolted rotor with curvic couplings of the turbine end of a heavy duty gas turbine was built. A method of accurately applying the preload force has been studied in this article. The three-dimensional finite-element contact method was used, non-linear behaviours such as friction and contact were also taken into account, and the dynamic contact between the spindle bolts and the sidewall of turbine wheels was included. The tendency of stress, which involved the rotor, curvic couplings, and the spindle bolts, was determined and the radial slippage trend of curvic teeth was also determined, by investigating the stress distribution and contact behaviour of the bolted rotor with curvic couplings during the course of preload, warm-up, speed-up, and running. It can be seen from the results that the contact stress of curvic couplings is dominant during the course of preload, and the bent stress is dominant when the rotating speed increased to 3000 r/min; the stress inequality on two sides of a tooth is caused by torque, so the stress proportion induced by torque should be restricted to an appropriate level to avoid anisotropy of the rotor.

The purpose of this study is to compare the efficacy of laparoscopy-assisted radical gastrectomy (LARG) versus that of open radical gastrectomy (ORG). Clinical data of 355 patients who underwent radical gastrectomy (160 in the LARG group and 195 in the ORG group) were analyzed retrospectively. Efficacy indices were compared and analyzed between the two groups. The operating time of LARG was longer than that of ORG (228.43 ± 34.77 versus 207.59 ± 28.39 min). However, patients in the LARG group lost less blood than did those in the ORG group (169.46 ± 82.92 versus 193.86 ± 82.09 mL), and more lymph nodes were removed in the LARG group (19.84 ± 4.7 versus 18.04 ± 4.14 per case). The recovery of intestinal function was faster (3.72 ± 1.03 versus 4.41 ± 1.30 days) in the LARG group. Patients in the LARG group were administered a semi-fluid diet earlier (5.66 ± 2.27 versus 7.09 ± 2.33 days) and had a shorter hospital stay (9.44 ± 3.06 versus 11.07 ± 7.91 days) than did those in the ORG group, and these differences were statistically significant (P0.05). No significant differences were found in the length of proximal and distal resection margin and the incidence of complications (P0.05) between the two groups. Thus, LARG is safe, feasible, and effective for treating advanced gastric cancer.

This paper presents an active and reactive power dynamic optimization model for active distribution network (ADN), whose control variables include the output of distributed generations (DGs), charge or discharge power of energy storage system (ESS) and reactive power from capacitor banks. To solve the high-dimension nonlinear optimization model, a new heuristic swarm intelligent method, namely wolf pack algorithm (WPA) with better global convergence and computational robustness, is adapted so that the network loss minimization can be achieved. In this paper, the IEEE33-bus system is used to show the effectiveness of WPA technique compared with other techniques. Numerical tests on the modified IEEE 33-bus system show that WPA for active and reactive multi-period optimization of ADN is exact and effective.

Photonic memristors, which behave as memristors operating with electromagnetic fields, present an effective means to achieve all-optical networking, and can promote the development of optical communications and computer technology. In this paper, we report a microwave memristive phenomenon at room temperature in metamaterials consisting of negative temperature coefficient thermistor ceramic disk and split-ring resonator (SRR). Hysteretic transmission-incident field power loops, the area of which varies with the scan rate of power, (similar to the fingerprint of memristors) were observed in the metamaterials. These effects are attributed to the increasing conductivity of the ceramic disk with increasing temperature generated by the interaction between electromagnetic waves and metamaterials. This work offers new opportunities for the development of photonic memristors.

Peroxisome proliferator activated receptor gamma (PPAR-γ) agonists are involved in the regulation of inflammatory responses and recent studies suggest that PPAR-γ ligands may have potential for the treatment of allergic airway disease. This study investigated the effect of the PPAR-γ agonist, rosiglitazone, on nasal mucous allergic inflammation and galectin-3 gene expression in a murine model of allergic rhinitis (AR mice). Rosiglitazone resulted in a statistically significant attenuation of the increased numbers of inflammatory cells and Th2 cytokine levels in nasal cavity lavage fluid of AR mice. Furthermore, the expression of galectin-3 in the nasal mucosa of AR mice was statistically significantly increased. Over-expression of galectin-3 was markedly suppressed by rosiglitazone treatment. These data suggest that the PPAR-γ agonist, rosiglitazone, may have potential in the development of therapies for allergic rhinitis.

Experimental data have suggested that BM-cell implantation can improve infarcted cardiac function. However, the number of implanted cells that survive is still unknown. The present study was performed to investigate whether implantation of autologous BM mononuclear cells (BM-MNCs) transfected with phVEGF165 can increase the number of surviving implanted cells, and enhance functional improvement of infarcted hearts in rabbits.Acute myocardial infarction (AMI) in rabbits was replicated by ligating the left anterior descending coronary artery, and animals were randomly divided into the following three groups: I AMI control group (n=7); II BM-MNCs transfected with phVEGF165 implantation group (n=7); III BM-MNCs implantation group (n=7). In addition, sham-operated (n=5) rabbits were randomly selected to serve as a non-infarction control group (VI). Animals for cell implantation received intramyocardial injections of autologous BM-MNCs 14 days after AMI. Echocardiography and hemodynamic studies were performed to evaluate cardiac structure and function 28 days after implantation. The implanted sites were examined using immunofluorescence to identify the phenotypes and number of the labelled cells. Reverse transcriptase (RT)-PCR and Western blot analysis were performed to detect the expression of hVEGF165 gene and VEGF165 protein respectively.Failed cardiac function produced by AMI was significantly improved in Groups II and III 28 days after cell implantation. BM-MNCs transfected with phVEGF165 implantation conferred a further improvement of cardiac function, with significant changes of all assessed parameters when compared with BM-MNCs implantation alone (all P0.05). The implanted cells demonstrated myogenic differentiation with the expression of Troponin T and organized contractile proteins. The positive staining for Factor VIII-related Ag indicated the induction of angiogenesis in the infarct area. The percentage of Brdu-positive myocyte, endothelial cells was 75+/-%, 34.1+/-4.6% in Group II, significantly higher than that in Group III(51+/-7%, 11.3+/-2.5% respectively, P0.05). RT-PCR analysis demonstrated exclusive expression of hVEGF165 gene in Group II, and Western blot showed the expression of VEGF165 protein was significantly higher in Group II than in Group III (P0.05).Implantation of BM-MNCs transfected with phVEGF165 can increase the number of implanted cells surviving, and enhance the impaired cardiac function after AMI.

Development plan and some progress have been made for amplifier of SGIII laser facility. According to this plan, a single-segment amplifier has been designed and experimented to test key units and correct simulating code in National Laboratory of Laser Fusion of China. The preliminary design for 4 X 2 X 3 amplifier prototypes, including amplifier modules, pulsed power, assembly equipment, and optics for SGIII will be finished.