Ryan H. Smith

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The parasitic dwarf mistletoeArceuthobium vaginatum attacksPinus ponderosa as its primary host andP. contorta as an occasional host. Within ponderosa pine stands there is also differential parasitism among individual trees. We compared biochemical features of phloem and xylem oleoresin between infected individuals of the two pine species (N=15 for each(More)
When African violet leaf explants are cultured in vitro, buds and shoots develop directly from the upper leaf surfaces. Three developmentally different African violet chimeras were cultured, and in each case adventitious shoots that developed into plants had the parent chimera pattern. A multicellular origin of the adventitious buds accounts for these(More)
A " black water " event, as observed from satellites, occurred off southwest Florida in 2012. Satellite observations suggested that the event started in early January and ended in mid-April 2012. The black water patch formed off central west Florida and advected southward towards Florida Bay and the Florida Keys with the shelf circulation, which was(More)
Chainpur and similar, apparently primitive, chondritic meteorites may be precursors of ordinary chondrites; a variety of evidence supports this working hypothesis. In general, carbonaceous chondrites seem to be related collaterally to this genetic sequence rather than being direct ancestors of ordinary chondrites. Metamorphic processes may be responsible(More)
Genetic effects associated with space flight include mutation induction by the space flight itself, and enhancements or antagonisms of radiation-induced mutations. The conditions of space flight vary in mutagenic effectiveness from no response at all to responses nine times that found in ground-based controls. The test systems follow the sensitivity(More)
Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumental neutron activation analysis of two Apollo 12013 rock fragments, a sample of rock 12013,17 sawdust, and a Java tektite (J2). Although the abundances of major elements in tektite J2 are similar to those of rock 12013, comparison of the minor and trace elements(More)
Since the interaction of the parasitic wasp Habrobracon with the space environment could not be prejudged, we decided to test approximately 30 different parameters of a genetic, mutational, biochemical, behavioral, and physiological character in the one spaceflight we had at our disposal. These parameters were examined at six different exposures of(More)