Lee W. Johnson

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Abstract Ecotilling was used as a simple nucleotide polymorphism (SNP) discovery tool to examine DNA variation in natural populations of the western black cottonwood, Populus trichocarpa, and was found to be more efficient than sequencing for large-scale studies of genetic variation in this tree. A publicly available, live reference collection of P.(More)
Introduction: The concept of a crewed mission to a Near-Earth Object (NEO) has been analyzed in depth in 1989 as part of the Space Exploration Initiative [1]. Since that time two other studies have investigated the possibility of sending similar missions to NEOs [2,3]. A more recent study has been sponsored by the Advanced Programs Office within NASA's(More)
Throughout our country, states and communities are struggling with the complex challenges of ensuring the safety and well-being of children in the child welfare system, and many states, including Florida, are experimenting with various types of privatization of child welfare services. This evaluation report examines the status of Community-Based Care (CBC)(More)
AND SUMMARY Autonomous Intelligent Vehicle Initiative (IVI) systems (which include in-vehicle forward-and side-looking sensors) can be supplemented by vehicle-vehicle and vehicle-highway cooperative and, if possible, passive elements to comprise a " sensor-friendly " highway environment that would enhance the operational efficiency, and ultimately, the(More)
A class of low nonlinearity dispersion-shifted and dispersion-flattened fibers for broadband and long haul applications is presented. The refractive index profiles of these fibers assume a depressed-core multi-clad geometry in order to achieve effective-areas much larger than those in conventional optical fibers. A systematic approach for designing large(More)
The Satellite Irrigation Management Support (SIMS) project combines NASA's Terrestrial Observation and Prediction System (TOPS), Landsat and MODIS satellite imagery, and reference evapotranspiration from surface weather station networks to map daily crop irrigation demand in California in near real time. TOPS-SIMS currently maps crop fractional cover, basal(More)