“Simultaneous nitrification and denitrification (SND) was


“Simultaneous nitrification and denitrification (SND) was realized by means of a novel air-lift internal loop biofilm reactor, in which aeration was set in middle of the reactor. During operation, the

aeration was adjusted to get appropriate Screening Library purchase dissolve oxygen (DO) in bulk solution and let aerobic and anoxic zone coexist in one reactor. When aeration was at 0.6 and 0.2 L/min, corresponding to DO of 5.8 and 2.5 mg/L in bulk solution, ammonia nitrogen removal percentage reached about 80 and 90 %, but total nitrogen removal percentage was lower than 25 %. While the aeration was reduced to 0.1 L/min, aerobic and anoxic zones existed simultaneously in one reactor to get 75 % of ammonia nitrogen and 50 % of total nitrogen removal percentage. Biofilms were, respectively, taken from aerobic and anoxic zone to verify their function of nitrification and denitrification in two flasks, in which ammonia nitrogen was transferred into nitrate completely by aerobic biofilm, and nitrate was removed more than 80 % by anoxic biofilm. Microelectrode selleck was used to measure the DO distribution inside biofilms

in anoxic zone corresponding to different aerations. When aeration was at 0.6 and 0.2 L/min, DO inside biofilm was more than 1.5 mg/L, but the DO inside biofilm decreased to anoxic status with depth of biofilm increasing corresponding to aeration of 0.1 L/min. The

experimental results indicated that SND could be realized because of simultaneous existence of aerobic and anoxic biofilms in one reactor.”
“Objective: To estimate the prevalence of 25(OH) vitamin D deficiency in children undergoing (adeno)tonsillectomy.

Methods: From 1st November 2008 to 20th December 2008,33 children aged from 4 to 16 and resident in Auckland, New Zealand (latitude 36 degrees 52` S) undergoing (adeno)tonsillectomy for difficulty breathing/sleep apnoea and/or recurrent tonsillitis had 25(OH) vitamin D, PRIMA-1MET molecular weight iron and zinc levels measured.

Results: Of the 32 patients who had 25(OH) vitamin D levels measured, 15.6% were vitamin D deficient (25(OH) vitamin D < 50 nmol/L), and 78% had levels, < 75 nmol/L 25(OH) vitamin D level was inversely correlated with Fitzpatrick skin type (Spearman’s rho = -0.713, p < 0.01), body mass index (BMI) (Spearman’s rho = -0.434, p = 0.013) and tonsil size (Spearman’s rho = -0.417, p 0.017). However regression modeling demonstrated that only Fitzpatrick skin type (beta = -0.687, p = 0.001) and BMI (beta = -0.256, p = 0.044) were significant predictors of vitamin D levels (R(2) = 0.572).

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