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Background and objective It has been proven that cancer cell autophagy can be induced by hypoxia. In addition, autophagy was correlated with radiosensitivity. Thus, regulating the autophagy signaling pathway is a potential treatment strategy. The aim of this study is to investigate the effects of combined autophagy inhibitor 3-methyladenine (3-MA) on the radiosensitivity of human adenocarcinoma A549 cells in hypoxia condition. Methods A549 cells were cultured in hypoxia condition, and then divided into two groups: hypoxia group and 3-MA plus hypoxia group. Electronic microscopy was used to detect autophagosome levels at different time points. The expression of LC3 was examined by Western blot. The proliferation activity of A549 cells after radiotherapy (0 Gy, 2 Gy, 4 Gy, 6 Gy, 8 Gy, and 10 Gy) was determined with an MTT assay. Results Autophagosome formation and the LC3II/LC3I ratio increased under hypoxic conditions. After treatment with the autophagy inhibitor 3-MA, the quantity of autophagosomes and the LC3II/LC3I ratio decreased. The proliferative activity of the cells in the 3-MA plus hypoxia group was remarkably lower than that in the hypoxia group after treatment with radiotherapy. Conclusion The level of protective autophagy of A549 cells increased in hypoxia condition; thus, inhibiting autophagy improves the radiosensitivity of A549 cells.

By taking the characteristics of the structure of Piccolo algorithm RP permutation into consideration, a 3-round quantum distinguisher was proposed.Based on Grover meets Simon algorithm, the 6-round of quantum key recovery attack was given.The results show that the key can be recovered 56 bit with the time complexity 2 28 and the occupation of 464 qubit.Moreover, if attack rounds r＞6，the time complexity is 2 28+16(r-6), which is 1 2 68 of Grover quantum brute-force search.The time complexity of the proposed attack method is significantly reduced compared with Grover search and is also better than that of traditional cryptanalysis, which lays a foundation for the subsequent research on quantum attacks of lightweight block ciphers.

A new double-layer satellite network model for space networking was established and a routing algorithm based on topology control (TCRA) was proposed considering the advantages of low earth orbit and stationary earth orbit satellite networks.This model used virtual node strategy and satellite grouping idea,which regarded the coverage area of each low earth orbit satellite as a virtual node.The network took into account the influence of the polar area on the division of the satellite footprints,such that the upper management satellites can accurately acquire the topology of the lower satellites.Using the improved virtual node strategy,the time slices were superior to other network models in quantity,length and other aspects.Based on the network topology,stationary earth orbit satellites calculate routing for low earth orbit satellites,while low earth orbit satellites were responsible for forwarding data.The simulation results show that the routing algorithm is superior to other algorithms in average end-to-end delay and packet loss rate.

According to the characteristics of overpressure carbonate reservoirs of the Kenkiyak pre-salt oil field in the littoral Caspian Basin, cores were made artificially and the stress sensibility of matrix cores and cores with non-packed, semi-packed and fully packed fractures were analyzed. The method of gas measurement was used in the experiment. The confining pressure of the sample cores was first increased and then decreased. When the confining pressure became stable, porosity and permeability data from each pressure point were obtained to analyze stress sensibility of cores. The results showed that the stress sensibility of these four types of cores with a descending order is cores with non-packed fractures, cores with semi-packed fractures, cores with packed fractures, and matrix cores. With the decrease in packing degree of core fractures, the stress sensitivity of core permeability increased and the recovery degree of permeability decreased; the recovery degree of porosity and permeability of the matrix cores and cores with fully packed fractures was high with the recovery of pressure and these two types of cores showed elastic-plastic features. By contrast, the recovery degree of porosity and permeability of cores with partly packed and unpacked fractures was lower and these two types of cores showed plastic features. With the increase of confining pressure, the variation of porosity and permeability showed relatively regular exponential variations. Key words: carbonates, abnormally high pressure, stress sensitivity, fracture packing, permeability variation

Background and objective Livin is a novel inhibitor of apoptosis protein (IAP), recent studies showed it overexpresses in a variety of carcinomas including lung cancer and contributes much to the cancerous development. The objective of this study is to explore the expression of livin in tissues of lung cancer and its relationshipwith histological types, chemotherapy, Lymph node metastasis and to study its correlation with the expression of pro-caspase3 as well. Methods Expressions of Livin and caspase3 were detected by Western blot assay in lung cancer tissues as well as in controls. Results Livin was expressed in 15 of 27 lung cancer, significantly more than those in lung para-cancerous (1/5) or benign disease lung tissues (2/12) (P 0.05). Conclusion Livin are differently expressed in different histological types of lung cancer; High levels of livin expression do not relate to chemotherapy, lymph node metastasis (P >0.05). The levels of livin tends to be positively associated with those of accordingly pro-caspase3, it is presumed that livin could bind pro-caspase3 and suppress its activation.