To facilitate molecular genetic analysis of vertebrate development, haploid genetics was used to construct a recombination map for the zebrafish Danio (Brachydanio) rerio. The map consists of 401 random amplified polymorphic DNAs (RAPDs) and 13 simple sequence repeats spaced at an average interval of 5.8 centimorgans. Strategies that exploit the advantages of haploid genetics and RAPD markers were developed that quickly mapped lethal and visible mutations and that placed cloned genes on the map. This map is useful for the position-based cloning of mutant genes, the characterization of chromosome rearrangements, and the investigation of evolution in vertebrate genomes.

This study indicates that all newspapers are not created equal when it comes to informing citizens of issues before Congress. The nation's largest newspapers seem to do the best job of informing citizens. However, they are read by a minority of the population outside of their primary circulation areas.

The ease of isolating mutations in zebrafish will contribute to an understanding of a variety of processes common to all vertebrates. To facilitate genetic analysis of such mutations, we have identified DNA polymorphisms closely linked to each of the 25 centromeres of zebrafish, placed centromeres on the linkage map, increased the number of mapped PCR-based markers to 652, and consolidated the number of linkage groups to the number of chromosomes. This work makes possible centromere-linkage analysis, a novel, rapid method to assign mutations to a specific linkage group using half-tetrads.

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The production of 26 Al in novae is uncertain, in part, because of the uncertain rate of the 25 Al(p,γ) 26 Si reaction at novae temperatures. This reaction is thought to be dominated by a longsought 3 + level in 26 Si, and the calculated reaction rate varies by orders of magnitude depending on the energy of this resonance. We present evidence concerning the spin of a level at 5.914 MeV in 26 Si from the 28 Si(p,t) 26 Si reaction studied at the Holifield Radioactive Beam Facility at ORNL. We find that the angular distribution for this level implies either a 2 + or 3 + assignment, with only a 3 + being consistent with the mirror nucleus, 26 Mg. Additionally, we have used the updated 25 Al(p,γ) 26 Si reaction rate in a nova nucleosynthesis calculation and have addressed the effects of the remaining uncertainties in the rate on 26 Al production.