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Tumor drug resistance (TDR) invariably leads to the failure of chemotherapy. In addition, current treatment strategies for TDR are not satisfactory due to limitations in terms of safety and feasibility. The aim of the present study was to determine whether low-intensity low-frequency ultrasound (LILFU) could improve the effect of chemotherapy and reverse TDR in gemcitabine-resistant ASPC-1 (ASPC-1/GEM) cells. The investigation focused on the association between LILFU effectiveness and the adenosine triphosphate-binding cassette (ABC) transporters and the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor (NF)-κB signaling pathway. A Cell Counting Kit-8 assay was used to determine the appropriate acoustic intensity, half-maximal inhibitory concentration of gemcitabine (GEM) and the viability of ASPC-1/GEM cells. ASPC-1/GEM cells were divided into control, GEM, LILFU and GEM+LILFU groups. Cell proliferation was evaluated through colony formation assays, whereas cell apoptosis was detected using flow cytometry. Western blotting was used to explore the expression levels of ABC transporters and PI3K/AKT/NF-κB signaling pathway-associated proteins. Xenograft models in mice were established to identify the enhancing effect of GEM+LILFU in vivo. Immunohistochemistry was used to detect the expression levels of Ki-67 in tumor tissues. The acoustic parameter of 0.2 W/cm2 and a GEM concentration of 6.63 mg/ml were used in subsequent experiments. Following treatment with GEM+LILFU, the cell viability and proliferation ability were decreased, whereas the apoptotic rate was increased compared with the GEM group. The expression levels of ABC transporters, PI3K-P110α and NF-κB were decreased in the GEM+LILFU group. Notably, LILFU increased the effectiveness of GEM in inhibiting tumor growth, and reduced the expression levels of Ki-67 in the xenograft mouse model. LILFU improved the chemosensitivity of ASPC-1/GEM cells via inhibition of cell viability and proliferation, and promoted cell apoptosis in the GEM+LILFU group. In conclusion, LILFU may downregulate the expression levels of ABC transporters by inhibiting the PI3K-p110α/AKT/NF-κB signaling pathway, thereby reversing resistance in pancreatic cancer.

Establish the mechanical model of wire knot which was formed by the automatic bundling machine, and the model is simulated by ANSYS. The method can simulate testing and evaluation the strapping characteristics, thus can provide the support to design and use bundling machine properly as well as improve the strapping quality of automatic bundling machine.

In this paper, we discuss the cooperation behaviors of intelligent virtual agents with autonomous and cooperative ability .Based on the theory of fluent calculus, we have designed an agent reasoning model .In this model, intelligent virtual agent could automatically judge the next action in the action queue and constructs the dynamic environment quickly with limited information from sensor. Furthermore, a type of request/server cooperation function has been designed for the cooperation among virtual agents to solve the conflicts and to realize the joint goals. Experiment results obtained demonstrated that intelligent virtual agents could cooperate well by our reasoning model.

In order to solve the problems that diagnosis cycle is very long and diagnostic accuracy is very low dependent on the maintenance man to diagnose fault by experience, an expert system for fault diagnose of a planes airborne electronic devices based on VC++ and CLIPS is proposed. The information exchange is realized between VC++ and CLIPS through writing external function of CLIPS by VC++ platform. The fact base can be generated quickly through acquiring test parameters from test model according to the fault information template base. The expert system established by VC++ platform to write man machine interface codes and load CLIPS to realize fault reasoning can realize the fast fault diagnosis for the airborne electronic devices.

In order to solve the problems that measuring efficiency is low and measuring precision is low dependent on the maintenance man to test by manual work, a universal high precision tester of attack and slide angle sensor is proposed. The measuring efficiency has improved through the electronic spirit level that measures the attack and slide angle fast and automatically and reads data automatically. The universal property and expansibility is realized by the design method that the software and test data are designed separately. The tester in this paper is fit for the fast maintenance requirement of the attack and slide in the army, and this method has certain reference to construct other electronics tester.

A design idea of calcium tester based on embedded platform is described. The composition of calcium test system is firstly analyzed. Secondly, in the acquisition of the potential signal of solution concentration the model of a sensor system is introduced. Finally the realization technique of tester is chiefly discussed in hardware and software.

Selective oxidation of sulfides was successfully performed by employing phenyliodine diacetate as an oxidant with the catalysis of TsOH in aqueous solution under mild conditions. Sulfoxides were formed with 1.1 equiv of PhI(OAc)2 at room temperature; whereas sulfones were obtained in the presence of 2.1 equiv of PhI(OAc)2 at 80 °C under otherwise identical conditions. Notably, various sulfides were converted to corresponding sulfoxides or sulfones in good to high yields by this metal-free protocol.

An efficient CuI-catalyzed carboxylation of terminal alkynes under mild conditions and without the need of any additional ligand is developed.

The oxidation of sulfides (I) with Oxone in ethanol leads to sulfoxides (II), while the oxidation in water affords sulfones (III) in high yields.