The Method for Inferring a Buried Fault from Resistivity Tomograms and Its Typical Electrical Features

Electrical resistivity tomography (ERT) has been used to experimentally detect shallow buried faults in urban areas in the past a few years, with some progress and experience obtained. According to the results from Olympic Park, Beijing, Shandong Province, Gansu Province and Shanxi Province, we have generalized the method and procedure for inferring the discontinuity of electrical structures (DES) indicating a buried fault in urban areas from resistivity tomograms and its typical electrical features. In general, the layered feature of the electrical structure is first analyzed to preliminarily define whether or not a DES exists in the target area. Resistivity contours in resistivity tomograms are then analyzed from the deep to the shallow. If they extend upward from the deep to the shallow and shape into an integral dislocation, sharp flexure (convergence) or gradient zone, it is inferred that the DES exists, indicating a buried fault. Finally, horizontal tracing is be carried out to define the trend of the DES. The DES can be divided into three types-type AB, ABA and AC. In the present paper, the Zhangdian-Renhe fault system in Zibo city is used as an example to illustrate how to use the method to infer the location and spatial extension of a target fault. Geologic drilling holes are placed based on our research results, and the drilling logs testify that our results are correct. However, the method of this paper is not exclusive and inflexible. It is expected to provide reference and assistance for inferring the shallow buried faults in urban areas from resistivity tomograms in the future.

Clinicopathological features of typical and nontypical hereditary non-polyposis colorectal cancer and their germline mutation of hMLH_1 and hMSH_2

Objective To study the clinicopathological features of the Chinese hereditary non-polyposis colorectal cancer and its germline mutation of hMLH1 and hMSH2. Methods Thirteen typical Chinese hereditary non-polyposis colorectal carcinoma (HNPC) C kindreds and 19 nontypical HNPCC families were registered and followed up. The germline mutation of the hMLH1 and hMSH2 of 12 index cases of 6 typical and 6 nontypical NHPCC were screened by PCR-SSCP. Samples with abnormal mobility were sequenced direcdy. Results The average age of typical HNPCC was 47, no difference existed between sexs. Location of the tumors of typical HNPCC represented 44.7% on the right half colon and non-typical HNPCC 65. 8% on the rectum. The rate of the metachronos cancer was 11.5%. The 3 - , 5 - and 10 -year survival rate was 64. 0%, 45. 3% and 31. 2% respectively. Among 12 cases, 8 showed abnormal mobility. Except for an intron polymorphinism, six exons abnormalities were found in 5 of 12 proband. Sequencing showed 4 missense,7