English holly culture in Oregon has been threatened by the
development of red leaf spots which prevent sale of cut holly.
Chemical, mechanical and insect injury and boron deficiency have
been shown in the past to cause different types of red leaf spotting,
but the cause of holly scab, a...
Certain plant-associated prokaryotes such as Corynebacteriurn
fascians and Agrobacterium tumefaciens are known to produce substantial
levels of cytokinins. In view of the fragmentary and
presumptive evidence available on the quantitative and qualitative
levels of cytokinins produced by A. tumefaciens, it was decided to
conduct a study of the cytokinins produced...
Using combined HPLC-RIA, cytokinin levels in a series of tobacco crown gall tumors, having altered morphologies as a result of transposon mutagenesis were examined. Average trans-ribosylzeatin levels in the shoot-producing tumors (tms mutants) and root-producing tumors (tmr mutants) were 1400 pmol/gm and 0.97 pmol/gm, respectively. Cytokinin/auxin ratios were highest in...
The purpose of the study was to compare the visual-motor performance
of college students who reported ingestion of certain drugs with
those college students who reported no drug ingestion. The study
drugs included the following drugs or groups of drugs: tobacco,
alcohol, marijuana, LSD, mescaline, barbiturates, and amphetamines.
A total...
Planarity has been successfully exploited to design faster and more accurate approximation algorithms for many graph optimization problems. The celebrated theorem of Kuratowski completely characterizes planar graphs as those excluding K_5 and K_{3,3} as minors. Kuratowski's theorem allows one to generalize planar graphs to H-minor-free graphs: those that exclude a...