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The hydrogen reduction behavior of iron oxide composite pellets containing Ni, Fe, and Mn from 973 K to 1173 K was compared with iron oxide and Al2O3 containing reference composite pellets to determine the effect of metallic species on the kinetics of iron oxide reduction. The Mn and Ni containing pellets showed slightly faster initial reduction rates compared to the Fe and Al2O3 containing pellets. The effect of the metal phases was found to be more significant at lower temperatures when chemical reaction at the interface is a slower and more controlling factor. From the SEM of partially reduced pellets, a wide intermediate region between an O rich unreacted core and an Fe rich outer shell was observed. Although an initially short topochemical receding interface controlled region exists, the mixed control between the topochemical receding interface and pore diffusion was prevalent. For Fe2O3/Mn composite pellets, the thermodynamic stability of the MnO is higher and Mn can act as a reductant for iron oxide. Thus, the overall metallization of the Fe2O3/Mn composite pellets decreased compared to the other Fe2O3/metal composite pellets. From the temperature dependence of the iron-oxide/metal composite pellets, the apparent activation energy was calculated to be approximately between 15 to 20 kJ/mol, which is typical of a mixed control reduction mechanism of gas diffusion and interface reaction. [ABSTRACT FROM AUTHOR]

This study was to estimate the predicted effect-site concentration of propofol administered by a target-controlled infusion (TCI) for maintenance of anesthesia based on the bispectral (BIS) index as a measure of hypnosis in laparoscopic surgery. One-hundred and sixty unpremedicated patients undergoing gynecologic laparoscopy were assigned randomly to receive one of the target effect-site concentrations of propofol 2.0, 2.5, 3.0, 3.5 and 4.0 μg/ml during TCI with propofol and sufentanil. The dose-response relationship of propofol for the maintenance of adequate anesthesia based on BIS, movement and hemodynamic response was investigated using a fixed effect-site concentration of sufentanil (0.2 ng/ml). The BIS values, hemodynamic variables, time course during emergence and intraoperative awareness were also assessed. The predicted effect-site propofol concentrations for adequate anesthesia at the skin incision in 50% (EC) and 95% (EC) of patients undergoing gynecologic laparoscopy were 2.2 and 3.7 μg/ml, respectively. The predicted propofol EC and EC to maintain adequate anesthesia in these patients were 2.6 μg/ml (95% CI 2.3-2.7 μg/ml) and 3.6 μg/ml (95% CI 3.3-4.0 μg/ml), respectively. The BIS values, effect-site concentration of propofol, hemodynamic data and time course during emergence and post-operative adverse events were comparable in each group. There were no reports of intraoperative awareness in the post-anesthetic care unit. Based on the anesthetic depth assessed by the clinical signs and BIS monitoring, the predicted effect-site propofol concentrations for the maintenance of anesthesia in patients undergoing gynecologic laparoscopy were similar in those administered adequate anesthesia at the skin incision during TCI. [ABSTRACT FROM AUTHOR]

We report the identification of novel allele HLA-DRB1*1478 that was found during routine high-resolution sequence-based typing of the cord blood unit in Korean population. The DRB1*1478 allele shows two nucleotide differences from DRB1*1463 in exon 2 at nucleotide position 344 (G→T) and 345 (T→G), resulting in an amino acid change, Gly86Val. [ABSTRACT FROM AUTHOR]

A novel human leukocyte antigen (HLA)-A allele has been identified in the cord blood of a Korean baby. New HLA-A*1135 allele was different from HLA-A*1131 by three nucleotide substitution at codon 142 (ATC→ACC) and codon 163 (CGG→ACG), resulting in two amino acid change, Ile 142 Thr and Arg 163 Thr. [ABSTRACT FROM AUTHOR]