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Method and apparatus for aligning a solar concentrator using two lasers

Description: A method and apparatus are provided for aligning the facets of a solar concentrator. A first laser directs a first laser beam onto a selected facet of the concentrator such that a target board positioned adjacent to the first laser at approximately one focal length behind the focal point of the concentrator is illuminated by the beam after reflection thereof off of the selected facet. A second laser, located adjacent to the vertex of the optical axis of the concentrator, is used to direct a second laser beam onto the target board at a target point thereon. By adjusting the selected facet to cause the first beam to illuminate the target point on the target board produced by the second beam, the selected facet can be brought into alignment with the target point. These steps are repeated for other selected facets of the concentrator, as necessary, to provide overall alignment of the concentrator.
Date: October 5, 2000
Creator: Diver, Richard Boyer Jr.
Partner: UNT Libraries Government Documents Department

Speech recovery device

Description: There is provided an apparatus and method for assisting speech recovery in people with inability to speak due to aphasia, apraxia or another condition with similar effect. A hollow, rigid, thin-walled tube with semi-circular or semi-elliptical cut out shapes at each open end is positioned such that one end mates with the throat/voice box area of the neck of the assistor and the other end mates with the throat/voice box area of the assisted. The speaking person (assistor) makes sounds that produce standing wave vibrations at the same frequency in the vocal cords of the assisted person. Driving the assisted person's vocal cords with the assisted person being able to hear the correct tone enables the assisted person to speak by simply amplifying the vibration of membranes in their throat.
Date: October 19, 2000
Creator: Frankle, Christen M.
Partner: UNT Libraries Government Documents Department

Modified cellulose synthase gene from 'Arabidopsis thaliana' confers herbicide resistance to plants

Description: Cellulose synthase ('CS'), a key enzyme in the biosynthesis of cellulose in plants is inhibited by herbicides comprising thiazolidinones such as 5-tert-butyl-carbamoyloxy-3-(3-trifluromethyl) phenyl-4-thiazolidinone (TZ), isoxaben and 2,6-dichlorobenzonitrile (DCB). Two mutant genes encoding isoxaben and TZ-resistant cellulose synthase have been isolated from isoxaben and TZ-resistant Arabidopsis thaliana mutants. When compared with the gene coding for isoxaben or TZ-sensitive cellulose synthase, one of the resistant CS genes contains a point mutation, wherein glycine residue 998 is replaced by an aspartic acid. The other resistant mutation is due to a threonine to isoleucine change at amino acid residue 942. The mutant CS gene can be used to impart herbicide resistance to a plant; thereby permitting the utilization of the herbicide as a single application at a concentration which ensures the complete or substantially complete killing of weeds, while leaving the transgenic crop plant essentially undamaged.
Date: October 11, 2000
Creator: Somerville, Chris R. & Scieble, Wolf
Partner: UNT Libraries Government Documents Department