Summary. Three hundred and sixty-seven strains of pioneer streptococci isolated from the mouths of 40 healthy, full-term infants during the first month of life were examined by two taxonomic schemes that incorporated biochemical and physiological characteristics, IgAl protease production and glycosidase activities. Streptococcus mitis biovar 1 and S. oralis comprised 55-0 YO of the pioneer streptococci isolated from neonates. S. salivarius constituted 25.3% of the isolates, while S. anginosus, S. mitis biovar 2, S. sanguis and S. gordonii accounted collectively for 1 1.4 % . Difficulties in identifying streptococci were encountered and 8.4% of the 367 isolates could not be assigned to a recognised species.

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The 3-megabase Igκ locus undergoes differentially controlled nuclear positioning events and chromatin structural changes during the course of B cell development. The temporal association of chromatin structural changes, transcription, and recombination at the Igκ locus was determined in a murine pre-B cell line that can be induced to recombine at the Igκ locus and in ex vivo-cultured murine pre-B cells. Additionally, the timing of nuclear positioning relative to the temporal order of chromatin structural changes and recombination and transcription was determined. We demonstrate that before induction, the Igκ locus was poised for recombination; both alleles were in a contracted state, and the enrichment of histone modifications and germline transcripts of specific Vκ genes were observed. Histone modifications of the Vκ genes did not vary upon induction but the levels of modifications correlated with the levels of germline Vκ gene transcripts and recombination. Upon induction, but before VκJκ recombination, centromeric recruitment of single Igκ alleles occurred. DNase I sensitivity of the entire locus increased gradually over the course of differentiation while the enrichment of histone modifications downstream of the Vκ genes was increased in the silencer regions upstream of Jκ1, within the Igκ sterile transcript, the κ constant region, the Eκi and Eκ3′ enhancers, and the recombining sequence. The ex vivo pre-B cells showed similar patterns of histone modifications across the locus except at the Vκ genes. In this study, H3 acetylation correlated with levels of germline transcripts while H3 methylation correlated with levels of recombination.

Accurate monitors are required to determine ambient concentration levels of contaminants emanating from concentrated animal feeding operations (CAFOs), and accurate models are required to indicate the spatial variability of concentrations over regions affected by CAFOs. A thorough understanding of the spatial and temporal variability of concentration levels could then be associated with locations of healthy individuals or subjects with respiratory ailments to statistically link the presence of CAFOs to the prevalence of ill health effects in local populations. This workgroup report, which was part of the Conference on Environmental Health Impacts of Concentrated Animal Feeding Operations: Anticipating Hazards—Searching for Solutions, describes instrumentation currently available for assessing contaminant concentration levels in the vicinity of CAFOs and reviews plume dispersion models that may be used to estimate concentration levels spatially. Recommendations for further research with respect to ambient air monitoring include accurately determining long-term average concentrations for a region under the influence of CAFO emissions using a combination of instruments based on accuracy, cost, and sampling duration. In addition, development of instruments capable of accurately quantifying adsorbed gases and volatile organic compounds is needed. Further research with respect to plume dispersion models includes identifying and validating the most applicable model for use in predicting downwind concentrations from CAFOs. Additional data are needed to obtain reliable emission rates from CAFOs.

The SuperTIGER (Super Trans-Iron Galactic Element Recorder) instrument was developed to measure the abundances of galactic cosmic-ray elements from 10 Ne to 40 Zr with individual element resolution and the high statistics needed to test models of cosmic-ray origins. SuperTIGER also makes exploratory measurements of the abundances of elements with 40 < Z 60 and measures the energy spectra of the more abundant elements for Z 30 from about 0.8 to 10 GeV/nucleon. This instrument is an enlarged and higher resolution version of the earlier TIGER instrument. It was designed to provide the largest geometric acceptance possible and to reach as high an altitude as possible, flying on a standard long-duration 1.11 million m 3 balloon. SuperTIGER was launched from Williams Field, McMurdo Station, Antarctica, on 2012 December 8, and made about 2.7 revolutions around the South Pole in 55 days of flight, returning data on over 50 × 10 6 cosmic-ray nuclei with Z 10, including ∼1300 with Z > 29 and ∼60 with Z > 49. Here, we describe the instrument, the methods of charge identification employed, the SuperTIGER balloon flight, and the instrument performance.