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We have succeeded in magneto-optical trapping of Yb atoms decelerated by a Zeeman slower method. The number of the trapped atoms is more than about 1.3ϫ10 6 measured by light absorption. We have found the evidence of the branching from the 1 P 1 excited state to triplet states, and determined the lower limit on the branching ratio to be 1.2ϫ10 Ϫ7 .

Chemical compositions are determined based on high-resolution spectroscopy for 137 candidate extremely metal-poor (EMP) stars selected from the Sloan Digital Sky Survey (SDSS) and its first stellar extension, the Sloan Extension for Galactic Understanding and Exploration (SEGUE). High-resolution spectra with moderate signal-to-noise (S/N) ratios were obtained with the High Dispersion Spectrograph of the Subaru Telescope. Most of the sample (approximately 80%) are main-sequence turn-off stars, including dwarfs and subgiants. Four cool main-sequence stars, the most metal-deficient such -3stars known, are included in the remaining sample. Good agreement is found between effective temperatures estimated by the SEGUE stellar parameter pipeline, based on the SDSS/SEGUE medium-resolution spectra, and those estimated from the broadband (V − K) 0 and (g − r) 0 colors. Our abundance measurements reveal that 70 stars in our sample have [Fe/H] < −3, adding a significant number of EMP stars to the currently known sample. Our analyses determine the abundances of eight elements (C, Na, Mg, Ca, Ti, Cr, Sr, and Ba) in addition to Fe. The fraction of carbon-enhanced metal-poor stars ([C/Fe]> +0.7) among the 25 giants in our sample is as high as 36%, while only a lower limit on the fraction (9%) is estimated for turn-off stars. This paper is the first of a series of papers based on these observational results. The following papers in this series will discuss the higher-resolution and higher-S/N observations of a subset of this sample, the metallicity distribution function, binarity, and correlations between the chemical composition and kinematics of extremely metal-poor stars.

Strategies that were adopted during the process development of Cefotetan in order to achieve a cost-effective commercial-scale synthesis are described herein. These included replacement of the trifluoroacetic acid used for cleavage of the benzhydryl ester and the development of an alternative synthetic route. This work led to improvement of both the impurity profile and the yield of the process. The pilot-scale synthesis of Cefotetan is described in detail in the Experimental Section. The scaled-up process has been successfully used for the commercial manufacture of Cefotetan since 1983.

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