Objective In order to increase significantly the discriminatory potential of Y-STR systems available to the forensic community , We have developed and validated a four-color fluorescence multiplex PCR system consisting of 7 male-specific and polymorphic Y-STRs. Methods We designed three sets of constant primers chimerited into three groups of 7 Y-STR's specific primers and utilized fluorescence- labeled these three sets of constant primers to amplified simultaneously 7 Y-STRs in a reaction tube. Allele and haplotype frequencies at these Y-STRs were screened by ABI PRISM310 Genetic Analyzer and analyzed by Genotyper software. Results Following optimization of the polymerase chain reaction , DYS434, Y-GATA-A10,DYS531, DYS557 , DYS456 , DYS444 and DYS448 in a sample of 120 unrelated males , showed4, 5, 5, 8, 8, 6,7 alleles respectively. A total of 101 different haplotypes was identified,of which 89 (88. 11% ) were found in single individuals. The overall haplotypes diversity reached 0.9958. To the one case of mixture stains, our multiplex system drawn conforming conclusion comparing to the result of Y-STR genotypes in suspect's blood sample. Conclusion Our results show that the multiplex system of 7 Y-STR will be very powerful for establishing Y-STR database, the paternity testing and mixture stains identifying.

Objective:To investigate the effect of different cleaning methods on the cleaning effect of Da Vinci robotic electrosurgical instruments and the feasibility of adenosine triphosphate(ATP) fluorescence detection technology for evaluating the cleaning effect of Da Vinci robotic electrosurgical instruments.Methods:A total of 180 electrosurgical instruments were divided into control group and test group by random digits table method from June 2018 to June 2019 after robotic surgery. For the control group, 90 cases were manually cleaned to complete the device cleaning process, and for the test group, 90 cases were mechanically cleaned to complete the device cleaning process. Through visual observation, magnifying glass examination and ATP fluorescence detection technology, the cleaning effect of the two methods and the correlation between the evaluation results obtained by ATP fluorescence detection technique and traditional inspection method were compared.Results:The qualified rate of visual observation, magnifying lens examination and ATP fluorescence detection in the control group were 95.56%(85/90), 86.67% (78/90) and 84.44% (76/90), respectively, and that in the test group were 100.00% (90/90), 97.78% (88/90) and 98.89% (89/90), respectively. The test group was higher than the control group. The difference between the two groups was statistically significant ( χ2 values were 4.310, 7.745, 12.291, P<0.05 or 0.01). In the control group, there was a positive correlation between the qualified rate of ATP fluorescence detection and visual observation ( r value was 0.374, P < 0.01), and a significant positive correlation between the qualified rate of magnifying lens examination ( r value was 0.538, P < 0.01). In the test group, There was also a significant positive correlation between the qualified rate of ATP fluorescence detection and visual observation ( r value was 0.754, P < 0.01), and between the qualified rate of magnifying lens examination( r value was 0.556, P < 0.01). Conclusions:Mechanical cleaning is used to clean Da Vinci robotic electrosurgical instruments, which is superior to traditional manual cleaning. ATP fluorescence detection technology is feasible for evaluating the cleaning effect of Da Vinci robotic electrosurgical instruments.