4 research outputs found
Cloned cattle derived from a novel zona-free embryo reconstruction system
As the demand for cloned embryos and offspring increases, the need arises for the development of nuclear transfer procedures that are improved in both efficiency and ease of operation. Here, we describe a novel zona-free cloning method that doubles the throughput in cloned bovine embryo production over current procedures and generates viable offspring with the same efficiency. Elements of the procedure include zona-free enucleation without a holding pipette, automated fusion of 5-10 oocyte-donor cell pairs and microdrop in vitro culture. Using this system, zona-free embryos were reconstructed from five independent primary cell lines and cultured either singularly (single-IVC) or as aggregates of three (triple-IVC). Blastocysts of transferable quality were obtained at similar rates from zona-free single-IVC, triple-IVC, and control zona-intact embryos (33%, 25%, and 29%, respectively). In a direct comparison, there was no significant difference in development to live calves at term between single-IVC, triple-IVC, and zona-intact embryos derived from the same adult fibroblast line (10%, 13%, and 15%, respectively). This zona-free cloning method could be straightforward for users of conventional cloning procedures to adopt and may prove a simple, fast, and efficient alternative for nuclear cloning of other species as well
WISE Albedos for Tens of Thousands of Main Belt Asteroids
Using thermal IR data from the Wide-field Infrared Survey Explorer (WISE) mission we have calculated diameters for tens of thousands of previously known Main Belt asteroids. Using archival optical observations we have also determined albedos for each object. We present our results from this investigation including: diameter and albedo population statistics for the Main Belt as a whole; preliminary size-frequency and albedo distributions for dynamical families; and new populations of very high albedo asteroids. These results provide new insight into the surface chemistry and formation history of the Main Belt asteroids. Funding for this work was provided by the NASA Postdoctoral Program, administered through Oak Ridge Associated Universities. WISE is a joint project between UCLA and JPL funded by the NASA MIDEX program. The NEOWISE enhancement is funded through NASA Planetary Science