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We examined the gravitropic responses of surgically altered primary roots of Zea mays to determine the route by which gravitropic inhibitors move from the root tip to the elongating zone. Horizontally oriented roots, from which a 1-mm-wide girdle of epidermis plus 2-10 layers of cortex were removed from the apex of the elongating zone, curve downward. However, curvature occurred only apical to the girdle. Filling the girdle with mucilage-like material transmits curvature beyond the girdle. Vertically oriented roots with a half-girdle' (i.e. the epidermis and 2-10 layers of the cortex removed from half of the circumference of the apex of the elongating zone) curve away from the girdle. Inserting the half-girdle at the base of the elongating zone induces curvature towards the girdle. Filling the half-circumference girdles with mucilage-like material reduced curvature significantly. Stripping the epidermis and outer 2-5 layers of cortex from the terminal 1.5 cm of one side of a primary root induces curvature towards the cut, irrespective of the root's orientation to gravity. This effect is not due to desiccation since treated roots submerged in water also curved towards their cut surface. Coating a root's cut surface with a mucilage-like substance minimizes curvature. These results suggest that the outer cell-layers of the root, especially the epidermis, play an important role in root gravicurvature, and the gravitropic signals emanating from the root tip can move apoplastically through mucilage.

The object of this research was to determine how effectively the actions of a clinostat and a fluid-filled, slow-turning lateral vessel (STLV) mimic the ultrastructural effects of microgravity in plant cells. We accomplished this by qualitatively and quantitatively comparing the ultrastructures of cells grown on clinostats and in an STLV with those of cells grown at 1 g and in microgravity aboard the Space Shuttle Columbia. Columella cells of Brassica perviridis seedlings grown in microgravity and in an STLV have similar structures. Both contain significantly more lipid bodies, less starch, and fewer dictyosomes than columella cells of seedlings grown at 1 g. Cells of seedlings grown on clinostats have significantly different ultrastructures from those grown in microgravity or in an STLV, indicating that clinostats do not mimic microgravity at the ultrastructural level. The similar structures of columella cells of seedlings grown in an STLV and in microgravity suggest that an STLV effectively mimics microgravity at the ultrastructural level.

Columella cells of seedlings of Zea mays L. cv. Bear Hybrid grown in the microgravity of orbital flight allocate significantly larger relative-volumes to hyaloplasm and lipid bodies, and significantly smaller relative-volumes to dictyosomes, plastids, and starch than do columella cells of seedlings grown at 1 g. The ultrastructure of columella cells of seedlings grown at 1 g and on a rotating clinostat is not significantly different. However, the ultrastructure of cells exposed to these treatments differs significantly from that of seedlings grown in microgravity. These results indicate that the actions of a rotating clinostat do not mimic the ultrastructural effects of microgravity in columella cells of Z. mays.

Primary roots of Zea mays L. cv. Tx 5855 treated with fluridone are strongly graviresponsive, but have undetectable levels of abscisic acid (ABA). Primary roots of the carotenoid-deficient w-3, vp-5, and vp-7 mutants of Z. mays are also graviresponsive despite having undetectable amounts of ABA. Graviresponsive roots of untreated and wild-type seedlings contain 286 to 317 ng ABA g-1 f. wt, respectively. These results indicate that ABA is not necessary for root gravicurvature.

Although the Scopes trial remains the most famous court decision associated with the teaching of evolution, there have been many other more important court decisions associated with the teaching of evolution and creationism in public schools. An understanding of these decisions can help teachers answer students' questions about the teaching of evolution and creationism. Such an understanding can also be used to counter the antiscience attitudes and actions of creationist parents, school administrators, and colleagues.

The publication of Charles Darwin’s On the Origin of Species by Means of Natural Selection in 1859 began a scientific revolution that changed many people’s view of the world. Although Darwin’s ideas were controversial, in the United States he had a powerful advocate: Harvard’s Asa Gray, an evangelical Christian who was America’s leading botanist and president of the American Association for the Advancement of Science (of which William Jennings Bryan— one of John Scopes’s prosecutors—was a member). Gray, who helped arrange for the publication of Origin in the United States, was the only American taken into Darwin’s confidence before Origin was published (Larson 1989). Gray espoused a progressive, God-driven evolution of life. Although some people were disturbed by Darwin’s ideas, Gray’s reconciliation of God and evolution eased many people’s concerns about evolution (Scott 1994, Moore 1997). Gray’s First Lessons in Botany and Vegetable Physiology (1857; later renamed The Elements of Botany) was the leading botany textbook of the late 19th century and the first high school textbook after the publication of Origin to include Darwin’s ideas about evolution. Early in the 20th century the public’s concerns about evolution resurfaced, for by the end of World War I, religious attitudes in the United States had shifted. A perceived decline in morality, along with a collective longing for the seeming simplicity of prewar life, prompted many people to reexamine and increasingly rely on their religious faith for comfort and stability. Religious fundamentalism, based on a literal interpretation of the Bible, became increasingly popular. People who endorsed biblical literalism got their name—fundamentalists—from a series of 12 small pamphlets (containing 90 articles) entitled The Fundamentals that were written between 1910 and 1915. These pamphlets, whose publication was funded by Lyman and Milton Steward (the founders of the Union Oil Company), proclaimed biblical literalism as the antidote to “modernism.” Millions of the pamphlets were distributed (Larson 1989, Clouse 1995). In the 1920s, fundamentalists tried to translate their beliefs into political reform and thereby save the nation’s morality. After a successful crusade to outlaw liquor, fundamentalists set out to eliminate discussions of evolution in public schools. Led by religious leaders such as William Bell Riley, J. Frank Norris, and—most prominently—William Jennings Bryan, fundamentalists began a campaign that blamed Darwin’s ideas for the decline of the nation’s morality. Fundamentalist preachers such as Billy Sunday (a former Chicago Cubs outfielder) used theatrical services to link evolution with eugenics, prostitution, and crime; Aimee Semple McPherson presided at ritual hangings of “monkey teachers”; other preachers claimed that Darwin’s ideas promoted the four P’s: prostitution, perversion, pornography, and permissiveness

A popular technique for ending a plasmaetch process is to monitor the optical emissions from reaction species for gross changes. This at first appears to be a simple real‐time edge detection task. However, differences in plasma chemistry across runs, reactor chambers, and wafer patterns combine to make this control strategy quite problematic. Moreover, as exposed wafer areas continue to shrink, distinct end points become increasingly harder to identify. This new approach is simple, robust, and flexible. The application user trains elementary pattern detectors, or neurons, on a few representative process end point shapes. Software algorithms process the training end point data to find a range of resolutions for pattern recognition. The application then automatically builds a pattern detection network that tolerates signal noise, adapts to changing end point shape, and precisely registers process end points. The neural network end point detector has been successfully tested on a wide variety of data gathered over a period of many months. The application is currently calling end point in real time on several oxide etch processes at a major wafer fabrication facility.

A personal audio assembly including a pair of miniature speakers releasably connected with the sidepieces of a pair of spectacles or headgear in a manner permitting adjustment of the speakers longitudinally, angularly and vertically with respect to the sidepieces or headgear and toward and away from the ears of a user. Leads connect the speakers with an audio source controlling sound entering the ear and are provided with an adjusting member maintaining the speakers in a selected.

The effect of ABA on root growth, secondary-root formation and root gravitropism in seedlings of Zea mays was investigated by using Fluridone-treated seedlings and a viviparous mutant, both of which lack carotenoids and ABA. Primary roots of seedlings grown in the presence of Fluridone grew significantly slower than those of control (i.e. untreated) roots. Elongation of Fluridone-treated roots was inhibited significantly by the exogenous application of 1 mM ABA. Exogenous application of 1 micromole and 1 nmole ABA had either no effect or only a slight stimulatory effect on root elongation, depending on the method of application. The absence of ABA in Fluridone-treated plants was not an important factor in secondary-root formation in seedlings less than 9-10 d old. However, ABA may suppress secondary-root formation in older seedlings, since 11-d-old control seedlings had significantly fewer secondary roots than Fluridone-treated seedlings. Roots of Fluridone-treated and control seedlings were graviresponsive. Similar data were obtained for vp-9 mutants of Z. mays, which are phenotypically identical to Fluridone-treated seedlings. These results indicate that ABA is necessary for neither secondary-root formation nor for positive gravitropism by primary roots.