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Radiotherapy is an important treatment method for malignant tumors. Radiation resistance is the main obstacle to the therapeutic effect of radiotherapy. Cellular metabolic reprogramming is one of the main features of cancer, and it may have an important effect on the therapeutic effect of radiotherapy. Glutamine is closely related to tumor cell biosynthesis and growth. It affects radiotherapy sensitivity by producing antioxidants through decomposition. In addition, the expression patterns and functions of two isoenzymes of glutamine, namely, glutaminase (GLS) and glutaminase 2 (GLS2), are different and have an important influence on the sensitivity of radiotherapy. The utilization of glutamine metabolism in the tumor microenvironment has great research value to improve the efficacy of radiotherapy. This review describes the metabolic characteristics of glutamine in malignant tumors and the sensitization effect of glutamine inhibitors on the efficacy of radiotherapy.

Routing and guiding acoustic waves without diffraction broadening and backscattering losses is of great interest to the acoustic community. Here, we propose a diffraction-immune acoustical waveguide based on diffraction inhibition in 2D sonic crystals (SCs). Due to the flat equal-frequency contour, the propagating acoustic waves can be highly localized between two neighboring rows of SCs. A few integrated sonic circuit building blocks including arbitrary angle bends and power splitters are further designed and theoretically realized. The proposed SCs open up possibilities for the flexible control of acoustic waves and lead to applications in integrated acoustical devices.

Based on transmission line theory and impedance transition, we design an ultra-wideband Transverse ElectroMagnetic (TEM) horn antenna that takes advantage of index gradient structure and loading techniques and is optimized for highway Ground Penetrating Radar (GPR) applications. We use numerical simulation to analyze the effects of different curved surfaces as an extension of the antenna and further improve the antenna performance by the use of a metallic reflective cavity and distributed resistor loading. We then fabricated an antenna based on the optimization results and determined the Voltage Standing Wave Ratio (VSWR) of the antenna to be less than 2 for bandwidths ranging from 0.9–12.6 GHz. The waveform fidelity of the antenna is also good and when we applied this antenna to highway scenarios, it achieved good results.

[Objectives] Ship conceptual design requires the coordination of many different disciplines for comprehensive optimization, which presents a complicated system design problem affecting several fields of technology. However, the development of overall ship design is relatively slow compared with other subjects. [Methods] The decomposition and coordination strategy of ship design is presented, and the analytical target cascading (ATC) method is applied to the multidisciplinary design optimization of the conceptual design phase of ships on this basis. A tank ship example covering the 5 disciplines of buoyancy and stability, rapidity, maneuverability, capacity and economy is established to illustrate the analysis process in the present study. [Results] The results demonstrate the stability, convergence and validity of the ATC method in dealing with the complex coupling effect occurring in ship conceptual design.[Conclusions] The proposed method provides an effective basis for optimization of ship conceptual design.

Stair-climbing function of Micro Mobile Robot（ MMR） conflict with their portability. The Beijing Institute of Technology has developed a four-wheeled MMR which can climb stairs by flipping chassis. This robot weights 2. 5kg,so it is portable and can be deployed by throwing in short distance. In allusion to that robot,three concerns as well as assessments in dropping process have been put forward. The hyperelastic model of rubber and elastic-plastic model considering strain rate of metals were established,and a finite element model（ FEM） was established with ABAQUS furthermore. The FEM was tested on three typical working conditions of dropping horizontally,vertically and side-vertically by 1m height. Problems of the original structure were discussed and optimization measures were put forward,concerning tire,shell and motor shaft and so on.Simulation experiments have been done to confirm the validity of those measures. The results show that the dropping resistance is improved,and the optimized structure can sustain drops of 3 m.

Aiming at the shortcomings of the traditional fixed atmospheric environment monitoring system, such as low flexibility, limited monitoring space, and the limitation of the distance of the unmanned aerial vehicle (UAV) atmospheric environment monitoring based on the data transmission module and the limited amount of data transmitted online, the multi-rotor UAV atmospheric environment monitoring system transmitted by 4G network is designed, transmits the atmospheric data collected by the airborne atmospheric detection sensors to the network cloud server through the 4G network, and realizes real-time monitoring and analysis of atmospheric data on the data monitoring platform, combined with the transparent cloud and cloud configuration technology. Firstly, the shortcomings of traditional ground monitoring stations and drone monitoring methods were analyzed, and the overall design of the system is given; then, the software and hardware design of the system were expounded in detail; finally, experiments were carried out in in the university town of Hailing area of Taizhou city. The research results can effectively expand the working space and methods of traditional atmospheric environment monitoring and provide new ideas and methods for the research of environmental monitoring UAV.

In order to clarify the possibility of rearing razor clams (Sinonovacula constricta) in inland saline water (ISW) and to facilitate their breeding under these stressful conditions, we performed semi-static acute and chronic toxicity tests to determine the effects of carbonate alkalinity (CA) and pH on the survival and growth rate, and critical metabolic enzyme activity in juvenile of S. constricta (JSC). (1) Acute toxicity test. As the water CA increased from 1.22 to 45.00 mmol L-1, the survival rate decreased significantly, which was exacerbated by the increase in the pH. When the water CA was set at 2.5 mmol L-1, the 48 h lethal concentration 50% (LC50) for JSCs with respect to pH was 9.86. When the water pH was 9.0, 9.5, and 10.0, the 48 h LC50 values for JSCs with respect to CA were 10.38, 8.79, and 3.11 mmol L-1, respectively. (2) Chronic toxicity test. Four experimental groups comprising the control, CAS, pHS, and CA-pHS were designated according to the target ISW data. After 3 months of stress, the JSC survival rate in each group exceeded 85%, but survival was significantly lower in the CA-pHS group than the control group (p < 0.05) in the first month. For the JSCs in various groups, the shell length growth rate (SGR) and weight gain (WG) rate were significantly lower in the CA-pHS group than the other groups (p < 0.05 for SGR; p < 0.001 for WG) in the first month. However, the difference in the growth rate among groups decreased in the next 2 months. For the JSCs in the CA-pHS group, the oxygen consumption, ammonia-N excretion, Na+/K+-ATPase, aspartate aminotransferase, and superoxide dismutase levels were significantly higher than those in the other groups during the first month, but there were no significant differences between the groups subsequently. The acetylcholinesterase and lysozyme levels did not differ significantly among groups during stress for 3 months. The integrated biomarker response index showed that stressors comprising high pH and CA could be tolerated well by JSCs over long periods of stress. These results indicate that water CA and pH together affect the survival, growth, and physiological activity of JSCs. S. constricta is suitable for culture in ISW.

In order to effectively reduce the human-computer interaction (HCI) workload before the assembly process simulation in the digital assembly environment, and to enhance the intelligence of assembly sequence planning, we introduce the assembly constraint relationship into the automatic generation of assembly sequences and propose a practical assembly sequence planning method for intelligent assembly. Firstly, starting from the assembly geometry model, an assembly model liaison graph is constructed by combining the analysis of assembly constraint relationship and the definition of disassembly direction rules. Then, according to the liaison graph, disassembly priority constraint matrix based on constraint relationship is constructed, and the automatic generation and dynamic update of the disassembly priority diagram can be realized by the definition of disassembly doubly linked list. According to the diagram, the rationality of the disassembly sequence is determined through the interference check analysis, and then the assembly sequence is automatically generated from the reversed disassembly sequence. Finally, the method in the text is verified by an example case study.