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In the process of establishing routing in VANET, because of the interference of routing request (RREQ) and routing response (RREP), the nodes in the network are busy with looking for routing or establishing routing. The impact on the network performance is extremely serious, such as increasing a lot of network overhead, consuming valuable bandwidth resources. In this paper, the influence of routing replay attack in VANET is studied. Four typical characteristic are extracted by “cross layer” selecting feature vector. The feasibility of VANET routing replay attack IDS based on SVM is verified through simulation experiment.

With the development of science and technology, wireless sensor network (WSN) has been widely used in all walks of life. The security problem of WSN has become a research hotspot. Intrusion detection technology has an important position in the network security. In this Paper, firstly, the intrusion and intrusion detection are introduced, secondly, the WSN intrusion detection system and its classification are analyzed. The main study is to analyze the current WSN intrusion detection technology and their respective advantages and disadvantages. The development direction of WSN intrusion detection technology is put forward finally.

Objective: To analysis the expression profile of7 clock genes during mouse embryonic stem cell (mES) differentiation., Methods: Mouse ES cells of the line 129 were cultured and induced to differentiate into neurons by 5 stages method. The expression of 7 clock genes: BMAL1, CLOCK, CRY1, CRY2, PER1, PER2, and PER3 in the five stages were determined by RT-PCR., Results: In the amplification condition, no non-specific band was found, and only bands of expected sizes were detected. Six clock genes, BMAL1, CLOCK, CRY1, CRY2, PER1 and PER3 were expressed in 129 cells at all five stages in the differentiation process, however, PER2, could only be determined in the last stage., Conclusion: The transcription profile of the clock genes is different during the differentiation of the ES cells towards neurons. The transcription of the gene PER2 is limited to the final stage, when postmitotic neurons and astrocytes emerged. A clock genes loop existing in the mature cells has not been established during the process of ES cell differentiation.

Objective: To study the loss of heterozygosity (LOH) at chromosomes 1p or 19q in oligodendroglial tumors., Methods: Twenty-eight cases of oligodendroglial tumors were enrolled into the study. Real-time quantitative polymerase chain reaction-based microsatellite analysis was performed on paraffin-embedded tumor tissues in order to study the status of chromosomes 1p and 19q., Results: Among the 28 cases of oligodendroglial tumors, 24 cases (85.7%) showed 1p LOH, while 18 cases (64.3%) showed 19q LOH and 17 cases (60.7%) showed LOH of both 1p and 19q. LOH at 1p or 19q was present in 25 (89.3%) of the 28 cases., Conclusions: Real-time quantitative polymerase chain reaction-based microsatellite analysis is a rapid and specific way in detecting LOH in paraffin-embedded tumor tissues. LOH at 1p or 19q is present in majority of the oligodendroglial tumors studied.

Human B1F was cloned from a human liver cDNA library by yeast one-hybrid screening and characterized. It is a transcription factor which belongs to nuclear receptor superfamily. The cDNA segment 450-930 of human liver transcription factor hB1F was cloned into the pGEX-3X expression vector and was expressed in E.coli. The purified GST-fused hB1F, named GST-CS, were used to immunize mice to get polyclonal antibodies to hB1F. The antiserum showed specificity to hB1F after the purification by GST-Sepharose 4B. It can be used in further investigations of the structure and function of hB1F.