Douglas A. Johnson

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The genus Elymus (“Ryegrass”) is a repository for a range of species with a variety of haplome contents; hence the pejorative name “dustbin” genus. We have analyzed 1,059 sequences from 128 accessions representing 24 species to investigate the relationships among the StH haplomes-containing species described by Yen and Yang (Genus Elymus Beijing 5:58–362,(More)
Although seeds have been the subject of extensive studies for many years, their seed coats are just beginning to be examined from the perspective of molecular genetics and control of development. The seed coat plays a vital role in the life cycle of plants by controlling the development of the embryo and determining seed dormancy and germination. Within the(More)
Exposure-based treatments have proven effective in treating a range of fears and phobias and can be accounted for by mechanisms described in behavioral theory. Enhanced dosed and dosed-only exposure are promising new behavioral approaches for treating fears and phobias. Thirty-nine participants with speech anxiety were randomly assigned to a prolonged(More)
* The views in this article are the author's and do not necessarily reflect those of the USAID. Abstract The rangelands of the Tibetan steppe cover an extensive area of Asia, which is comprised of a diversity of cold deserts, semiarid steppes, shrublands, alpine steppes, and moist alpine meadows. The climate of these rangelands is strongly continental, and(More)
The genus Dasypyrum contains two species: the annual and widespread D. villosum (2x = 2n = 14) and the perennial and generally rare D. breviaristatum (2x = 2n = 14 and 4x = 2n = 28). The origin of the latter and its genome constitution have been subject of several studies. There is agreement that the genome of the diploid D. villosum (VV) is different from(More)
The study of proportional relationships between size, shape, and function of part of or the whole organism is traditionally known as allometry. Examination of correlative changes in the size of interbranch distances (IBDs) at different root orders may help to identify root branching rules. Root morphological and functional characteristics in three range(More)
Dasypyrum is a genus with two species, an annual diploid Dasypyrum villosum and a perennial diploid or tetraploid D. breviaristatum. It is difficult to distinguish between the two, especially for a non-taxonomist. In this paper we demonstrate how to distinguish between the two species and between the two ploidy levels of D. breviaristatum. We achieve this(More)
Cereal infection by the broad host range fungal pathogen Fusarium graminearum is a significant global agricultural and food safety issue due to the deposition of mycotoxins within infected grains. Methods to study the intracellular effects of mycotoxins often use the baker's yeast model system (Saccharomyces cerevisiae); however, this organism has an(More)
Before the attacks of 9/11, the public policy issues surrounding the use of torture by the United States were simple: torture was immoral, illegal, and flatly prohibited. U.S. foreign policy and national security strategies mirrored and advanced this opposition to torture. This changed on September 11, 2001. Angered by the attacks and fearing further loss(More)