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How often will elections end in landslides? What is the probability for a head-to-head race? Analyzing ballot results from several large countries rather anomalous and yet unexplained distributions have been observed. We identify tactical voting as the driving ingredient for the anomalies and introduce a model to study its effect on plurality elections, characterized by the relative strength of the feedback from polls and the pairwise interaction between individuals in the society. With this model it becomes possible to explain the polarization of votes between two candidates, understand the small margin of victories frequently observed for different elections, and analyze the polls'' impact in American, Canadian, and Brazilian ballots. Moreover, the model reproduces, quantitatively, the distribution of votes obtained in the Brazilian mayor elections with two, three, and four candidates. 相似文献
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Michitaro Nagasawa James Amigo Chan Charles J. Sih 《Prostaglandins & other lipid mediators》1974,8(3):221-230
Prostaglandins E1, F1α and A2 were covalently joined to the surface of Sepharose as carboxamide linkages. The insolubilized prostaglandins were shown to function effectively in the purification of 15(S) -hydroxyprostaglandin dehydrogenase. 相似文献
88.
Charles Drechsler 《American journal of botany》1960,47(5):368-377
Drechsler , Charles . (Plant Industry Sta., Beltsville, Md.) Two new species of Conidiobolus found in plant detritus. Amer. Jour. Bot. 47(5) : 368—377. Illus. 1960.–By canopying Petri plates of maize-meal agar with small quantities of friable or mealy plant detritus 2 new species of Conidiobolus, both of moderate dimensions, were isolated. They are described as C. incongruus and C. multivagus. The former, obtained from leaf mold collected in Colorado, produces zygospores which with respect to their internal organization differ markedly from those of congeneric species but resemble rather closely the globuliferous zygospores of Basidiobolus haptosporus and B. meristosporus. Conidiobolus multivagus, obtained from decayed twigs of Casuarina equisetifolia gathered in western Florida, forms a mycelium that soon becomes conspicuously disconnected. The disconnected condition here results partly from the production of many detached slender filaments, which, by constantly withdrawing protoplasmic materials from the posterior end while elongating at the tip, migrate through the slated substratum apparently without any intake of nutrients. The detached conidia of C. incongruus are provided with a more prominent basal papilla than those of C. multivagus, though both species show equally sharp demarcation between the globose main contour of the conidium and the dome-shaped contour of the papillia. 相似文献
89.
Pseudomonas aeruginosa and P. denitrificans accumulate more protoheme and considerably more protoporphyrin during anaerobic growth under denitrifying conditions than during aerobic growth. In Escherichia coli, the small accumulation of protoporphyrin and protoheme which occurs during anaerobic growth is slightly stimulated by nitrate and markedly stimulated by oxygen. 相似文献
90.
Mutants of Escherichia coli K12 which accumulated the haem precursor porphobilinogen are described. The mutants grew very slowly on carbon and energy sources which K12 uses only oxidatively, and they had low catalase activities, suggesting that they were deficient in haem. Extracts had one-tenth of the parental activity of the enzyme porphobilinogen deaminase. In transduction, the mutation mapped close to genes ilvD and metE at minute 84. The gene was tentatively identified as hemC, coding for porphobilinogen deaminase. The gene symbol hemC replaces the earlier and temporary symbol popE. 相似文献