Refine
Year of publication
- 1996 (84) (remove)
Document Type
- Article (84) (remove)
Language
- English (84) (remove)
Has Fulltext
- yes (84)
Keywords
Institute
- SFB 268 (20)
- Physik (6)
- Informatik (5)
- Biowissenschaften (3)
- Mathematik (2)
- Biochemie und Chemie (1)
- Extern (1)
- Exzellenzcluster Die Herausbildung normativer Ordnungen (1)
- Gesellschaftswissenschaften (1)
- Institut für Ökologie, Evolution und Diversität (1)
- Medizin (1)
- Rechtswissenschaft (1)
- Universitätsbibliothek (1)
- Wirtschaftswissenschaften (1)
A non-radioactive cell-free assay was developed to quantitatively determine inhibition of plant-type phytoene desaturase by bleaching herbicides. An active desaturase was prepared from an appropriately cloned E. coli transformant. Another E. coli transformant was used to produce the required phytoene. Phytofluene and t-carotene, the products of the desaturase reaction, were either determined by HPLC or optical absorption spectra. Enzyme kinetics and inhibition data for the bleaching tetrazole herbicide WL110547 are presented as an example.
Cucumber plants (Cucumis sativus L.) were grown under controlled conditions and fumigated with either O3, diluted automobile exhaust or a combination of both. The ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) was estimated as a measure of PSII activity Activities of the enzymes catalase, glutathione reductase and guaiacol-dependent peroxidase and contents of the antioxidants ascorbate and glutathione were assayed as potential indicators of oxidative stress. The behavior of catalase and of PSII are of particular diagnostic interest because they require continuous repair in light. Exposures of up to 13 days to moderate concentrations of the pollutant gases alone did not induce striking changes in any of the activities that were assayed. A lso when the plants were subjected to an additional stress treatment by exposing them to 4 short cold treatments (2h each at 0 - 4 °C in light on days 12-15 after sowing) which induced marked declines of the Fv/Fm ratio, the chlorophyll content and the catalase activity, these cold-induced symptoms of photodamage were not significantly enhanced by the fumigation treatments. However, increases of the activities of glutathione reductase and peroxidase observed during a period of recovery following the cold-exposures were markedly higher in O3-fumigated plants, as compared to plants grown in filtered air or fumigated with car exhaust alone. The results emphasize that effects of moderate pollutant exposures may be latent or delayed over long time periods and that defence responses can be enhanced when plants are exposed to additional, naturally occurring stress situations.
The NA35 experiment used several independent methods to determine the strange particle production in p+S and S+A collisions. The different techniques show consistent results. Strangeness conservation in full phase space is used as an additional check of the consistency of the data.
On the base of the analysis in full phase space it could be shown that strangeness conservation is fullfilled. The NA35 K0S in S+S and S+Ag are consistent with the NA44 results for K+ and K−. The results of the NA36 collaboration for S+Pb collisions were extrapolated to full phase space. The comparison with the NA35 results shows more than two times lower yields. The ratio of Λ to Λ¯¯¯¯ at midrapidity of NA36 is inconsistent with the high baryon density determind by NA35. The strange particle production is compared to the abundance of non strange particles, especially negatively charged pions which are measured in full phase space in the same experiment. A clear enhanced strange hadron production relative to π− is observed in S+Ag collisions compared to p+S reactions at the same energy. The K0S multiplicity in full phase space per negative hadron (h−) in S+S, S+Ag and Pb+Pb is enhanced by about a factor 1.6 compared to N+N and p+S collisions. The NA36 result for the K0S multiplicity per h− in S+Pb is below the N+N value.
One of the most striking and unsettling elements in Venedikt Erofeev's novel "Moskva-Petuški" is the ending where Venja, the protagonist-narrator, is murdered by four mysterious executioners in the stairway of a downtown Moscow building. [...] The last sentence turns the entire preceding narrative into a paradox: the narrator indicates that he could not have told his story, since he ceased to exist as a consciousness ("soznanie") as soon as the action stopped. The fact of Venja's death itself does not necessarily cancel out his ability to tell about the events leading up to his demise: literature knows a number of beyond-the-grave narrators, e.g., the murdered Olivia in Anne Hebert's "Les fous de Bassan" or the dead samurai Tekehiko in Akutagawa Riunosuke's "In a grove". What makes Venja's narrative paradoxic is his own reference to the end of his cogitative activity. at the moment of death the hero ceases to think and should, logically, lose the ability to narrate. Normally, a dead narrator acquires his/her ability to narrate by supernatural means, e.g., via life after death, as in "Les Fous de Bassan" or through a medium, as in "In a Grove". Such postmortem loquacity may also remain unexplained. In "Moskva-Petuški", however, the dead narrator seems to stress that his death appears as the ultimate end: a point where everything, including time and consciousness, stops.
Ten years after writing "Spotted dog running along the seashore" ("Пегий пес, бегущий краем моря") Chingiz Aitmatov said that this novella was his favorite. Perhaps this is because it represents the essence of Aitmatov's artistic world view. The term "essence" is appropriate here because the setting and the characters of the novella are totally removed from the modem world and from history itself. Unburdened by the need to relate his artistic goals and philosophical interests to any specific socio-political context - a requirement made all the more problematic for an author writing within the Soviet literary system - Aitmatov was free to develop his favorite themes in a kind of "tabula rasa" medium. Thus, it was with absolute directness that the author could face questions dominating much of his fiction: the moral soundness of age-old values, the need for continuity in social development, the necessity of humanity's hannonious coexistence with nature, and the positive ethical value of myth.
Errata
(1996)
In the article "Secalonic acid A from Pseudoparmelia sphaerospora (Nyl.) Hale and P. hypomilta (Fée) Hale (Parmeliaceae)", published in Tropical Bryology 10: 201-204, 1995, the sentence at page 201 "Seven isomers are known of secalonic acid: A, B, C, D, E, F, and G, all isolated from fungi by Budavari (1989)" should read: ""Seven isomers are known of secalonic acid: A, B, C, D, E, F, and G, all isolated from fungi (Budavari 1989)".
Five species of the genus Cheilolejeunea are reported from Hong Kong. Among them, Cheilolejeunea osumiensis (Hatt.) Mizut. and Cheilolejeunea ryukyuensis Mizut. are new to China. Cheilolejeunea intertexta (Lindenb.) Steph. is newly reported for China except Taiwan, and Cheilolejeunea trifaria (Reinw. et al.) Mizut. is documented for the first time for mainland China except Hainan and Taiwan. The detailed description and illustration of Cheilolejeunea osumiensis as well as the key to the five Cheilolejeunea species of Hong Kong are also presented.
Aldabra Atoll, in the Republic of Seychelles, lies 450 km to the north of Madagascar and 650 km to the east of the Tanzanian coast of Africa (9o24’S, 46o20’E). It is one of the largest atolls in the world, with four main islands and numerous islets, totalling 97 km2. The underlying limestone is slightly raised, but is generally less than 8 m in elevation, and varies substantially in texture due to erosion. The atoll has been elevated above sea level for at least 80,000 years. Soils are generally shallow and alkaline (Trudgill 1979). The geology and ecology are outlined in Westoll and Stoddart (1971), Stoddart and Westoll (1979), and Stoddart (1984).