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BACKGROUND: As a special residue containing zinc and manganese, spent Zn-Mn batteries cause a serious concern due to their toxicity, abundance and permanence in the environment, and biotechnological recovery of Zn and Mn is one method of recycling thiswaste. In this study identification of the optimum values of the effective parameters in biotechnological processes was investigated using response surfacemethodology. RESULTS: The released dose of Zn andMnwas highly dependent on many parameters. Non-linear equationswere formulated to describe the relationship between bioleaching efficiency of Zn andMn and four important parameters. The optimum parameter values were determined as follows: dose of mixed energy substrates, exogenous-acid pH adjustment, incubating temperature and pulp density of 28 g L-1, 1.9, 33 °C, 9.7%, respectively, for Zn release and 29 g L-1, 1.8, 36.7 °C, 8%, respectively, for Mn mobilization. Themaximum predictive extraction efficiency of Zn andMn was 52.5% and 52.4%, respectively. CONCLUSION: The maximum efficiency of extraction of both Zn andMn reached 50% under optimum conditions after 9 days of bioleaching. Additionally, XRD analyses suggested that Zn andMn existed mainly as Hetaerolite (ZnMn2O4) in the spent Zn-Mn batteries, which gradually disappeared and released Zn2+ and Mn2+ into solution during bioleaching process. [ABSTRACT FROM AUTHOR]

Objective: To investigate the performance of revised trauma score (RTS), CRAMS score (circulation, respiration, abdomen, motor and speech) and prehospital index (PHI) on evaluation of injury severity in earthquake victims., Methods: Data of victims admitted to West China Hospital of Sichuan University during the Lushan earthquake from April 20th, 2013, to April 27th were retrospectively analyzed. The clinical information at admission was recorded, and the injury severity score (ISS), RTS, CRAMS and PHI were calculated. The optimal cut-off values were looked for, the comparability between the three scores and ISS score were figured out by receiver operator characteristic curve (ROC curve), and the correlation between ISS and three scores was analyzed by linear regression analysis., Results: There was a total of 263 victims included in the study. ISS ≥ 16 was found in 86 cases, and ISS<16 in 177 victims, and there were significant statistic differences in male ratio (67.4% vs. 50.8%, χ² = 6.477, P=0.011), RTS score [7.55 (0.29) vs. 7.84 (0), U=6 825, P=0.013] and CRAMS scores [8 (1) vs. 9 (1), U=3 977, P=0.000] between two groups. It was showed by ROC curve analysis that the area under the ROC curve (AUC) of RTS, CRAMS and PHI was 0.547 (P=0.220), 0.734 (P=0.000) and 0.544 (P=0.250), and the Youden indexes of the three scores were 0.093, 0.443, and 0.119, respectively. Moreover, the best cut-off values of them were 4.9, 9.5 and 3.5. Linear regression analysis showed that RTS and CRAMS score showed negative correlation with ISS score (r₁=-0.139, P₁=0.024; r₂=-0.413, P₂=0.000), while PHI showed no relationship with it (r=0.071, P=0.250)., Conclusions: Of these three scoring systems, CRAMS has the best correlation with ISS, and it can be used in the prompt assessment of trauma severity in earthquake victims.