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  • 1980-1984  (3)
  • FIR laser  (1)
  • Meliponinae  (1)
  • Nicotiana (cAMP)  (1)
  • 1
    ISSN: 1432-2048
    Keywords: Adenosine-3′:5′-cyclic monophosphate ; Nicotiana (cAMP) ; Zea (cAMP) ; Phaseolus (cAMP)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Direct evidence has been obtained for the presence of adenosine-3′:5′-cyclic monophosphate (cAMP) in tobacco (Nicotiana tabacum L.) callus tissue cultures, bean (Phaseolus vulgaris L.) seedlings and immature kernels of sweet corn (Zea mays L.) through the use of a highly specific and sensitive gas chromatography-mass spectrometric assay. Levels of endogenous cAMP ranged from 70 to 126 pmol/g fresh weight. Corresponding levels of cAMP determined for the same samples using radioimmunoassay were consistently three to four times higher. Contrary to previous reports for citrus plants, measurable levels of cAMP could not be detected in young lemon leaves within the limits of detection of the mass-spectrometric assay method. In the case of tobacco callus tissue, the coumarin glucoside, scopolin, which was present in large amounts and showed similar chromatographic behaviour to cAMP, interferred strongly with the mass-spectrometric measurements of cAMP in inadequately purified extracts. The use of high-performance liquid chromatography, in addition to standard chromatographic purification methods, produced highly purified plant extracts for quantitation of cAMP and also provided a method for the separation of cAMP from its 2′:3′-isomer.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 8 (1982), S. 1167-1181 
    ISSN: 1573-1561
    Keywords: Alarm substance ; nest defense ; nerol ; mandibular gland ; Hymenoptera ; Apidae ; Meliponinae ; stingless bees ; Trigona fulviventris ; Apiomerus pictipes ; Hemiptera ; Reduviidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Bees of the genusTrigona and subgenusTrigona possess volatile materials in their mandibular glands, used as alarm substances and as marking pheromones. Heads of workers ofTrigona fulviventris were analyzed by gas chromatography-mass spectrometry. The two major volatile components were nerol (∼ 50%), and octyl caproate (∼ 20%). Relative to other substances tested at a Costa Rican nest, treatments containing 20 μg of nerol attractedT. fulviventris, depressed numbers of bees leaving the nest by about 50%, and elicited wing vibration and biting. The responses were similar to those obtained with the contents of one worker head. Attraction and biting were also seen in response to captures of colony members by assassin bugs (Apiomerus pictipes) outside a nest entrance; one bee responded in about 15% of the captures. This alarm behavior, although weak, is of interest since it was thought thatT. fulviventris was unusual for its subgenus in its lack of nest defense behaviors.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    International journal of infrared and millimeter waves 1 (1980), S. 631-640 
    ISSN: 1572-9559
    Keywords: FIR laser ; interferometer ; plasma ; electron density ; vibration compensation ; quasi-optical Shottky diodes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A modulated far-infrared laser interferometer which is presently operating on the PDX experiment at Princeton is described. The interferometer geometry permits the characterization of inside “D”, outside “D” as well as circular discharges. To achieve this versatility, a titanium corner cube reflector, mounted inside the PDX vacuum vessel is used in conjunction with a second visible wavelength interferometer for vibration corrections. In addition, the use of room temperature quasi-optical Schottky diodes in the far-infrared interferometer is reported. The minimum detectable line average density of the system is ∼5×1011 cm−3.
    Type of Medium: Electronic Resource
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