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Abstract: A phylogenetic analysis of the archaeal community in the soil of the former Lake Texcoco showed that some of the clones identified were affiliated to Archeae that reduce nitrate (NO3 −) to nitrite (NO2 −) and NO2 − to unknown products under aerobic conditions. Previous research suggested that this indeed might occur when an easily decomposable C-substrate is available, but little is known about the factors that control the possible processes involved. The sandy clay loam soil with pH 10 and electrolytic conductivity 56dSm−1 was spiked with 1000mg glucose-Ckg−1 soil (GLUCOSE pre-treatment), 200mg NO3 −-Nkg−1 soil (NITRATE pre-treatment), or left unamended (CONTROL pre-treatment) and conditioned for eight days. Pre-treated soil was then added with 1000mg glucose-Ckg−1 soil and 200mg NO3 −-Nkg−1 soil and amended with ammonium (NH4 +) (AMM treatment) and l-glutamine (GLUT treatment), acetylene (C2H2) (ACE treatment), oxygen (O2) (OXI treatment), left untreated (CON treatment) or sterilized. No abiotic factors affected concentrations of NH4 +, NO2 − or NO3 −. In the CONTROL pre-treatment, concentration of NO3 − decreased 170mg Nkg−1 soil within 72h, in the GLUCOSE pre-treatment with 182mg Nkg−1 soil within 2h and in the NITRATE pre-treatment with 272mg Nkg−1 soil within 168h. Mean concentration of NO2 − was 3.2mg Nkg−1 soil in unamended soil, 5.7mg Nkg−1 soil in the CONTROL pre-treatment, but >20mgkg−1 soil in the GLUCOSE pre-treatment and ≥40mgkg−1 in the NITRATE pre-treatment. The application of NO3 − and glucose increased the mean concentration of NH4 + compared to the unamended soil independently of pre-treatment. It was found that microorganisms in the alkaline saline soil of the former Lake Texcoco can reduce concentrations of NO3 − while releasing NO2 − under aerobic conditions when an easy decomposable substrate is available without it being directly related to microbial activity and this being more outspoken when glucose or nitrate were previously added. [Copyright &y& Elsevier]

The purpose of this study was to evaluate the poly-axial locked plating system inserted through a minimally invasive approach for the treatment of three-part fractures of the proximal humerus. Twenty-three patients with a three-part fracture of the proximal humerus treated with a poly-axial locking plate through a percutaneous approach were available for clinical and radiological analysis at a minimum of 2 years follow up (average 36 months; range, 24-54 months). To assess objective and subjective outcomes the Constant Score (CS) and the Disabilities of the Arm, Shoulder, and Hand (DASH) score were obtained. All complications were recorded. There were 17 women and 6 men, with a mean age of 62 years (range, 18-86). All fractures healed. At final follow up, the mean forward flexion, external rotation and internal rotation were 126°, 44° and L1, respectively; the mean CS was 64 and the mean DASH score was 23. Twelve patients (52%) had a postoperative complication, which included screw cut-out, stiffness and infection. The poly-axial locked plating system through a minimally-invasive approach may be an appropriate treatment for three-part fractures of the proximal humerus and may reduce the biological aggression of conventional plate fixation. [ABSTRACT FROM AUTHOR]