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Metribuzin (MB), a triazinone herbicide is extensively sprayed for weed control in agriculture, has been reported to contaminate soil, groundwater, and surface waters. In soil, MB residues can negatively affect not only the germination of subsequent crops but also disturb soil bacterial community. The present study describes the use of biochar as a carrier material to immobilize MB-degrading bacterial consortium, for remediation of MB-contaminated soil and restoration of soil bacterial community in soil microcosms. The bacterial consortium (MB3R) comprised four bacterial strains, i.e., Rhodococcus rhodochrous AQ1, Bacillus tequilensis AQ2, Bacillus aryabhattai AQ3, and Bacillus safensis AQ4. Significantly higher MB remediation was observed in soil augmented with bacterial consortium immobilized on biochar compared to the soil augmented with un-immobilized bacterial consortium. Immobilization of MB3R on biochar resulted in higher MB degradation rate (0.017 Kd−1 ) and reduced half-life (40 days) compared to 0.010 Kd−1 degradation rate and 68 day half-life in treatments where un-immobilized bacterial consortium was employed. It is worth mentioning that the MB degradation products metribuzin-desamino (DA), metribuzin-diketo (DK), and metribuzin desaminodiketo (DADK) were detected in the treatments where MB3R was inoculated either alone or in combination with biochar. MB contamination significantly altered the composition of soil bacteria. However, soil bacterial community was conserved in response to augmentation with MB3R immobilized on biochar. Immobilization of the bacterial consortium MB3R on biochar can potentially be exploited for remediation of MB-contaminated soil and protecting its microbiota. [ABSTRACT FROM AUTHOR]

Abstract: Tribological performance of polyether ether ketone (PEEK) subjected to various heat treatments namely, annealing, normalizing, water quenching and oil quenching, respectively, after being heated to a temperature of 250°C is evaluated. It is observed that the different cooling rates have a significant effect on the crystallinity of PEEK which is found to be a governing factor in determining its mechanical and tribological properties. Micro hardness testing and ball‐on‐disk wear test results showed that both hardness and wear resistance increased with an increase in the crystallinity of PEEK. It is observed that the annealed samples showed the highest wear resistance when compared with the water‐quenched samples which is attributed to the increased crystallinity in the case of the annealed samples. [ABSTRACT FROM AUTHOR]

Objective: To determine the outcome of open reduction and internal fixation of supracondylar fracture of humerus in children using Flynn\'s criteria., Methods: The quasi-experimentalstudy was conducted at Punjab Medical College/Allied Hospital, Faisalabad, Pakistan from July 2012 to June 2014and comprised children aged between 5 and 12 years with supracondylar fracture of humerus presenting within one week of the fracture. Post-surgery follow-up included clinical assessment and measurement of carrying angle on radiographs. Outcome was assessed using Flynn\'s criteria. SPSS 17 was used for statistical analysis.., Results: Out of 79 cases, 50(63.3 %) were boys and 29(36.7%) girls. Overall mean age was 7.36±1.68 years. Excellent results were obtained in 58(73.4%), good in 14(17.7%), fair in 5(6.4%) and poor in 2(2.5%) patients in terms of functional and cosmetic outcome., Conclusions: Open reduction and internal fixation of supracondylar fracture was found to be a better choice of treatment with good functional results.