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81.
82.
Foraging-experienced honeybees retained normal flight, orientation, and memory functions after 30 minutes' exposure to 2.45-GHz CW microwaves at power densities from 3 to 50 mW/cm2. These experiments were conducted at power densities approximating and exceeding those that would be present above receiving antennas of the proposed solar power satellite (SPS) energy transmission system and for a duration exceeding that which honeybees living outside a rectenna might be expected to spend within the rectenna on individual foraging trips. There was no evidence that airborne invertebrates would be significantly affected during transient passage through microwaves associated with SPS ground-based microwave receiving stations. 相似文献
83.
L Larsson P M?rdh G Odham G Westerdahl 《Acta pathologica et microbiologica Scandinavica. Section B, Microbiology》1981,89(4):245-251
Gas chromatography/mass spectrometry and selected ion monitoring (SIM), employing both electron (EI) and chemical ionization (CI), was used to detect 10-methyloctadecanoic (tuberculostearic) and 2, 4, 8, 8-tetramethyloctacosanoic (C32 mycocerosic) acids in bacteria of 14 species of Mycobacterium and 3 species of Nocardia. Tuberculostearic acid was found in all species studied, while C32 mycocerosic acid was demonstrated only in M. africanum, M bovis, M. bovis strain BCG, M. kansasii and M. tuberculosis. The relative amounts of these acids in the organisms of these five species varied, thereby constituting a presumptive diagnostic technique. The lowest detectable amount of C32 mycocerosic acid was approximately 5 pg when using EI-SIM, monitoring at m/zz 88 and m/z 101. When using CI, employing isobutane as reactant gas, and focusing at m/z 495, 2 pg could be detected, and when ammonia was the reactant gas, the corresponding figure was 1 pg, monitoring at m/z 512. Tuberculostearic acid was demonstrated in 5-day incubated sputum specimens from 6 patients with pulmonary tuberculosis, including 5 patients infected with M tuberculosis and 1 patient infected with M. avium. C32 mycocerosic acid was detected in 4 of the 5 patients with M. tuberculosis infection. None of the acids was found in a further 8 patients who had viral or bacterial (non-mycobacterial) pneumonia. Tuberculostearic acid could be demonstrated in 10 of another 12 sputum specimens from patients with tuberculosis, when the samples were analyzed directly, viz prior to culturing. The possibility of using SIM for the rapid diagnosis of pulmonary tuberculosis is thus worth consideration. 相似文献
84.
C A Mancuso G Odham G Westerdahl J N Reeve D C White 《Journal of lipid research》1985,26(9):1120-1125
The glycerol diether phospholipids of 25 monocultures of methanogenic bacteria were isolated and degraded with hydriodic acid. The resulting alkyl iodides were converted to acetate esters and alcohols which were examined using capillary gas-liquid chromatography. The presence of C20 phytanol was observed in accordance with previous studies. Soft fragmentation by chemical ionization mass spectrometry combined with selected ion monitoring enabled the detection, for the first time, of C15 and C25 isoprenologues as components of the diether phospholipids in several strains. 相似文献