Co-Sputtered and Rapid-Thermal-Annealed CIAS Thin Films Using CuSe2/ln/Al Triple Targets of Varying Ln/Al Compositions.

The 20.9% conversion efficiency of I-III-VI chalcopyrite-based solar cells, the highest in the world, makes them promising candidates for high-efficiency thin film solar cells. However, Ga is one of the most expensive rare materials with the critical degradation in device efficiency. Cu(ln(1-X)Al(X))Se2 (CIAS) is considered an alternative to Cu(ln(1-X)Ga(X))Se2 because of its good structural suitability and the low cost of Al. CIAS thin films were formed using triple targets of CuSe2/ln/Al in a co-sputtering system to control the composition ratio, x = [Al]/([ln]+[Al), by varying each RF power for In/Al with rapid thermal annealing. The chalcopyrite peaks shifted toward higher 2theta as x increased. The CIAS thin films had 74.24-86.81% absorption with band gap, Eg, of 2.28-2.50 eV in the 400-1600 nm range. A low resistivity of 1.1 x 10(-2) omega(-cm) was obtained in the CIAS thin films with x of 0.74.

Retrospective analysis of the results of acellular pertussis vaccine toxicity tests performed in Korea.

Specific toxicity test is a major quality control test for acellular pertussis (aP) vaccines performed by manufacturers and regulatory authorities. The 'mouse body weight gain test (MWGT)', the 'leukocytosis-promoting test (LPT)' and the 'histamine sensitization test (HIST)' have been conducted to check the specific toxicity of all batches of aP vaccines used in Korea through the national quality control program, which requires a lot of animals, labor and time. In this study, test results obtained in the past 9 y from a total of 258 lots of aP vaccines were examined retrospectively to evaluate the three test methods. A pairwise comparison of the test results indicated a good correlation between LPT and HIST, whereas MWGT showed no correlation with either LPT or HIST. Moreover, the reversion to toxicity was higher than the residual toxicity in the majority of lots tested by HIST, which indicated that the histamine-sensitizing toxicity, although rated within a safe range, increased during the vaccine storage. Thus, the vaccine safety test results accumulated in the past might be useful for the improvement of test protocols.

Optimization of production of monacolin K from gamma-irradiated Monascus mutant by use of response surface methodology.

Monascus isolate number 711, which is capable of producing monacolin K as an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the key enzyme of cholesterol synthesis, was isolated from Ang-kak, the red yeast rice koji. To increase the monacolin K-producing activity of the strain, spore suspensions of the strain were subjected to gamma-irradiation. One thousand mutants were generated via gamma-irradiation and screened using bioassay and high performance liquid chromatography analysis. Several mutants with higher productivities of monacolin K than that of the parent strain were primarily selected. Mutant KU609 was finally selected because of its characteristics of high monacolin K production and non-citrinin-producing activity under our test conditions. Response surface methodology was used to analyze the effect of culture medium on the production of monacolin K in mixed solid-state cultures. The optimal values of nutritional ingredients for the maximal production were soytone, glucose, MgSO4, and barley at concentrations of 0.5 g, 0.48 g, 0.053 g, and 9 g, respectively. The final monacolin K production of Monascus KU609 was increased almost 100-fold compared to that of the parent strain.