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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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The emission maximum of the single tryptophan residue of melittin was measured in the presence of phosphatidylethanolamine liposomes and Escherichia coli cytoplasmic membranes. In both cases, the fluorescence maximum was shifted to shorter wavelengths indicating a transfer of the indole ring to an apolar environment. E. coli membranes were labelled in position 2 of their phospholipids with [14C]oleic acid. These membranes were used for measuring the activity of an endogenous phospholipase A2. A slow hydrolysis is observed, which can be accelerated by adding melittin. The extent of the stimulation depends on the molar ratio of melittin to membrane phospholipid. Under suitable conditions, the initial rate of hydrolysis is six to seven times higher in the presence than in the absence of melittin. The action of the phospholipase A2 from bee venom is also stimulated by melittin. An identical stimulation was observed with either E. coli membranes or pure phosphatidylethanolamine liposomes as substrate.  相似文献   
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Ohne ZusammenfassungEin Auszug dieser Arbeit erschien mit gleichlautendem Titel als Mitteilung Nr. 158 aus der Biologischen Versuchsanstalt der Akademie der Wissenschaften in Wien, Zoologische Abteilung, im Ak. Sitzungsanz. Nr. 17, 10. Juli 1930.  相似文献   
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Seventy-two Schiffs bases, 44 corresponding secondary amines, and 12 N-acetylated compounds were tested on their growth activity. Eighty-one compounds were active as growth inhibitors in at least one of three bioassays.  相似文献   
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The occurrence of bikunin and ·1-microglobuli n was investigated in human ovary and Fallopian tubes. Bikunin and ·1-microglobulin are transcribed in the liver from a common gene. Bikunin immunoreactivity was detected in the zona pellucida. A positive reaction for bikunin was also observed in connective tissue of the oviduct. In addition, mast cells showed a more intense posi tive reaction than the surrounding connective tissue. Specific displaceable ·1-microglobulin immunoreactivity was revealed in the zona pellucida. The data suggest that bikunin and ·1- microglobulin are trapped in the zona pellucida. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
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Herein, we disclose the discovery and optimization of 2-piperidin-4-yl-acetamide derivatives as MCH-R1 antagonists. Structural investigation of piperidin-4-yl-amide and piperidin-4-yl-ureas identified 2-piperidin-4-yl-acetamide-based MCH-R1 antagonists with outstanding in vivo efficacy but flawed with high affinity towards the hERG potassium channel. While existing hERG SAR information was employed to discover highly potent MCH-R1 antagonists with minimized hERG inhibition, additional hurdles prevented their subsequent clinical exploration.  相似文献   
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