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Abstract Objective The aim of this study was to assess the correlation of spouse selection with short tandem repeats (STRs) in DNA and with the number of fingertip lunulae to investigate the role of heredity in spouse selection. Methods We randomly selected a total of 286 couples (husband and wife) as a couple group while 200 paired subjects (a man randomly matched with a woman as a pair of subjects) were selected as a non-spouse group for DNA typing, and to investigate lunulae in spouse selection, a total of 554 couples were selected as a couple group and 500 pairs of subjects were selected as a control group. Results A significant difference of STR matching number (a large value implies a higher genetic similarity) between spouse group and non-spouse group were observed (12.3 ± 2.7 vs. 11.8 ± 2.6; p

To assess the efficacy of a mini-STR-based next-generation sequencing (NGS) method for non-invasive prenatal paternity testing (NIPPT).

In order to improve calculation efficiency of underground rock engineering parameters, displacement inversion calculation of rock mass parameters was carried out by orthogonal experiment. An optimal model of equivalent mechanical parameters of roadway rock mass was established taking elastic modulus, cohesion force, internal friction angle and tensile strength of rock mass as test parameters. Based on field monitoring data of －850 m horizontal soft rock haulage roadway in Qujiang Coal Mine, function relationship between step displacement and rock mass parameters was established accurately using the established numerical model for numerical analysis and regression analysis. The equivalent rock mass parameter identification results show that at the location of 1 500 m of the east roadway, the safety factor Fs is 0.97 under the original supporting condition, which is in unstable state, so it is necessary to re—strengthen the supporting. Finally, stability evaluation of －850 m horizontal east haulage reworking roadway in Qujiang Coal Mine was carried out. The monitoring data of the roadway in the test section shows that the mechanical strength of the surrounding rock mass after the repair of east roadway is greatly improved, and the safety factor Fs is 1.58, which shows the roadway is in a stable state. It is indicated that the repair scheme of 'screw, metal mesh, shotcrete, anchor cable, grouting and floor anchor cable' can well inhibit deformation of the roadway, which also verifies effectiveness of the rock mass mechanical parameter inversion method in soft rock roadway.

A fault disrupts the continuity of the rock strata in a mining area. To study the law governing the fracture of overlying strata in mining areas under discontinuous boundary conditions, the overlying strata were redefined and grouped based on the activity characteristics of each rock layer during the overall movement of the overlying strata. The activity patterns of different layers of the fault were obtained through the movement and failure forms of each group of rock layers. The relationship among the size of the coal pillar at the boundary of the fault, the dip angle of the fault, and the movement angle of the rock strata was considered. A model of the spatial relationship between the overlying rock movement zone of the quarry and the fault surface was established. The limit equilibrium equations of the key layer in the fault zone before breaking were established based on the tensile strength of the rock layer. In addition, the mechanical slip instability criterion and the deflection instability criterion of the discontinuous-boundary rock mass are given herein. Based on a field case, a double criterion was used to determine the initiating activated rock layers of the fault in the cases where the fault dip was smaller than the rock movement angle. Rock movement during excavation was simulated by similar simulation tests, and different levels of rock movement patterns in the boundary fault zone were focused on monitoring and analyzing. The stress and displacement changes in different rock layers in the fault zone were analyzed with numerical simulation results. The results show the following: if the dip angle of the fault is smaller than the movement angle of the rock layer, the delamination space of the fault surface is mainly distributed in the bending and sinking zone of the overlying rock; with an increase in the working-face advancement distance, the vertical pressure of the upper part of the fault gradually decreases, and the stress-concentration area in the middle and lower part of the fault gradually increases; the rock layer of the upper part of the fault, which is mainly composed of the key stratum, is the main area of activation of the fault. [ABSTRACT FROM AUTHOR]