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The mangrove killifish, Kryptolebias marmoratus, is unique among vertebrates due to its self-fertilizing mode of reproduction involving an ovotestis. As a result, it constitutes a simplistic and desirable vertebrate model for developmental genetics as it is easily maintained, reaches sexual maturity in about 100 days, and provides a manageable number of relatively clear embryos. After the establishment and characterization of an initial mutagenesis pilot screen using N-ethyl-N-nitrosourea, a three-generation genetic screen was performed to confirm zygotic mutant allele heritability and simultaneously score for homozygous recessive mutant sterile F2 fish. From a total of 307 F2 fish screened, 10 were found to be 1° males, 16 were sterile, 92 wild-type, and the remaining 189, carriers of zygotic recessive alleles. These carriers produced 25% progeny exhibiting several zygotic phenotypes similar to those previously described in zebrafish and in the aforementioned pilot screen, as expected. Interestingly, new phenotypes such as golden yolk, no trunk, and short tail were observed. The siblings of sterile F2 mutants were used to produce an F3 generation in order to confirm familial sterility. Out of the 284 F3 fish belonging to 10 previously identified sterile families, 12 were found to be 1° males, 69 were wild-type, 83 sterile, and 120 were classified as */+ (either wild-type or carriers) with undefined genotypes. This screen provides proof of principle that K. marmoratus is a powerful vertebrate model for developmental genetics and can be used to identify mutations affecting fertility.

Kryptolebias marmoratus is a synchronous hermaphroditic vertebrate that utilizes an ovotestis for reproduction. This fish develops externally, is easy to maintain, and has about a 100-day life cycle, making it a desirable developmental genetic model organism. Here, we present a pilot zygotic mutant screen utilizing the common chemical mutagen, N-ethyl-N-nitrosourea (ENU) to establish genetics in this model species. Selection of clonal stocks and optimal conditions for mutagenizing this fish are presented and the types and frequencies of zygotic mutants are documented in comparison to other fish models. Kryptolebias marmoratus is an exemplar model organism that will complement future developmental genetic screens in vertebrates.

The purpose of this document is to outline the K Basins 30 ton crane qualification strategy for use in the Spent Nuclear Fuel Project fuel relocation campaign.

The Radioisotope Thermoelectric Generator (RTG) Transportation System, designated as System 100, comprises four major systems. The four major systems are designated as the Packaging System (System 120), Trailer System (System 140), Operations and Ancillary Equipment System (System 160), and Shipping and Receiving Facility Transport System (System 180). Packaging System (System 120), including the RTG packaging is licensed (regulatory) hardware; it is certified by the U.S. Department of Energy to be in accordance with Title 10, Code of Federal Regulations, Part 71 (10 CFR 71). System 140, System 160, and System 180 are nonlicensed (nonregulatory) hardware.

Thermionic fuel element sheaths, seal and intercell insulators, and end restraints were irradiated in a fast neutron spectrum and examined. Samples were irradiated at temperatures ranging from 1110 K to 1200 K to fast fluences from 3.4×1022 n/cm2 to 6.0×1022 n/cm2. Sample examinations included visual, photographic, dimensional, electrical resistance to temperatures of 1175 K, helium leak rates, and metallography. Examinations of the end restraints and intercell insulators, which were limited to visual and photographic examination, showed no adverse effects from the irradiation. Alumina and yttria have been identified as insulator materials which meet design requirements.

Seven tasks are described which were designed to reach the objectives. At the time of termination of the grant, these tasks were in various stages of completion, as described in this report. Tasks 1 and 2: Experimental Verification of 'Torquewhirl'; Task 3: Measurement of the Alford Force; Task 4: Comparison of Test Data with Theory; Task 5: Inclusion of a More General Shaft Flexibility in the 'Torquewhirl' Theory; Task 6: Derivation of the Linearized Stiffness Damping, and Cross-Coupling for Use in a Computer Stability Analysis; and Task 7: Load-Dependent Stability Predictions for a Machine of Realistic Complexity. (Author)