Objective and Methods As a local species, Chinese rare minnow (Gobiocypris rarus) has been one of the standardized test fish for chemical toxicity tests in China .By optimal screening , the acute toxicity of potassium bichromate and 3,4-dichloroaniline (3,4-DCA) was determined to evaluate repeatability and accuracy for Gobiocypris rarus in one laboratory and between different laboratories .Result Based on a proper data analysis , for the two chemicals per-formed with the same fish, all 96 h LC50 values were within mean ( x-) and upper and lower control limits ( ±2s) in both inner test ( in one laboratory ) and outer test ( between different laboratories ) .Conclusions From these results , a valid database could also be established to evaluate one single test .In addition, Gobiocypris rarus will not only be a potential test species for ecotoxicity tests , but also recommended as a standard laboratory animal .

Objective: To explore the relationship between adolescents gratitude and social adaptation, as well as the mediating roles of school boding including support from teacher, peers and school belonging in the association. Methods: A total of 1 304 adolescents from 6 schools and colleges in Xuzhou were investigated with Adolescent Gratitude Scale, School Bonding Scale and Social Adaptation Scale. Results: Adolescent gratitude varied significantly in gender and grade, with girl’s gratitude significantly higher than that of boys(F=38.09, P<0.01). Adolescent gratitude increased as adolescents grew older, and was positively associated with social adaptation(r=0.26, P<0.01). School bonding partially mediated the relationship between adolescent gratitude with social adaptation(β=0.06). Conclusion School bonding plays a partial mediating role in the relationship between adolescent gratitude and social adaptation,adolescent gratitude can make a direct influence on social adaptation,and can also play an indirect role through school bonding.

Objective To investigate the effects of titanium dioxide ( TiO2 ) nanoparticles coupled with nuclear localization sequence ( NLS ) on the radiosensitivity of U251 glioma cells. Methods Synthesis and characterization of the TiO2-NLS nanoparticles with nuclear targeting property. U251 cells were treated with nanoparticles and/or ionizing radiation. Flow cytometry analysis was performed to measure the ROS content and the cell apoptotic percentage. The DNA damage was detected by using γ-H2AX foci staining. Clonogenic survival assay was used to evaluate the radiosensitivity of U251 cells. Results NLS modification promoted nuclear translocation of TiO2 nanoparticles. Compared with the control nanoparticles, TiO2-NLS treatment increased radiation-induced cell apoptosis (t=8. 96, P<0. 05). Clonogenic survival assay showed the radiosensitization ratios of TiO2 nanoparticle-treated group and TiO2-NLSnanoparticle-treated group were 1. 18 and was 1. 29, respectively. These two ratios had statistically difference ( t =14. 72, P< 0. 05). Conclusions Nuclear targeting TiO2 nanoparticles enhances the radiosensitivity of U251 glioma cells.

AIM: Previous studies have suggested that big stick design (BSD) method can only be used in clinical trials of two treatments with equal proportion, which has good statistical performance and has become the recommended choice of randomized methods. This study expands BSD method, so that it can be applied to three groups, and provides more randomized methods for clinical trials. METHODS: On the basis of BSD method used in two treatments with equal proportion, the derivation conditional allocation probability of BSD method used in three treatments with equal proportion was carried out. BSD method was compared with simple randomization (SR) method, permuted block design (PBD) method and block urn design (BUD) method by Monte-Carlo simulation in balance and randomness. RESULTS: In terms of balance, PBD method was the best, followed by BUD method, BSD method, and SR method was the worst. In terms of randomness, SR method was the best, followed by BSD method, BUD method and PBD method. The comprehensive performance showed that BSD method was better than BUD method, PBD method and SR method. CONCLUSION: The expanded BSD method used in three treatments with equal proportion has good comprehensive performance, and it can be the recommended randomization method for clinical trials of three treatments with equal proportion.