957 resultados para Colonization experiment


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We address ethical consumption using a natural field experiment on the actual purchase of Fair Trade (FT) coffee in three supermarkets in Germany. Based on a quasi-experimental before-and-after design the effects of three different treatments – information, 20% price reduction, and a moral appeal – are analyzed. Sales data cover actual ethical purchase behavior and avoid problems of social desirability. But they offer only limited insights into the motivations of individual consumers. We therefore complemented the field experiment with a customer survey that allows us to contrast observed (ethical) buying behavior with self-reported FT consumption. Results from the experiment suggest that only the price reduction had the expected positive and statistically significant effect on FT consumption.

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The so-called Dutch Pranketing Room of Alethea Talbot, Countess of Arundel, at Tart Hall was a site of domestic experiments, courtly splendour and global ambition. Lady Arundel, the probable author of a famous recipe book, would have used Tart Hall for cooking and experiments as well as for impressive dinner parties, and she would have used large amounts of sugar to create intricate imitations of meat and vegetables to astonish, entertain and delight her guests. Linking household practice with global trade as well as artistic creation, Lady Arundel’s banquets are situated not only between a national tradition of cooking, as it appears in Markham’s manuals, and the new possibilities the arising global trade provided, but also played with a mismatch between taste and sight. This mediating role could be compared to that played by the artists the Countess employed. Within this context it is worth noting that a series of paintings displayed in the building’s gallery showed still lifes, markets, and a cook. The inventory of Tart Hall gives an insight into the world of the widely travelled collector and patron of Van Dyck and Rubens, but raises also a number of questions. In my talk I would like to explore the Countess’ Pranketing Room as a site of mediation between alimentary and painterly experiments, considering the use of recipes, experience, invention and transformation

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In laboratory experiments, people are willing to sanction norms at a cost—a behavioral tendency called altruistic punishment. However, the degree to which these findings can be generalized to real-world interactions is still debated. Only a small number of field experiments have been conducted, and initial results suggest that punishment is less frequent outside of the lab. This study replicates one of the first field experiments on altruistic punishment and builds ties to research on norm compliance and the broken windows theory. The original study addressed the enforcement of the anti-littering norm in Athens. We replicate this study in Bern, Zurich, and New York City. As an extension, we investigate how the experimental context (clean vs littered) impacts social norm enforcement. As a second extension, we investigate how opportunity structure impacts the maintenance of the anti-littering norm. Findings indicate that norms are universally enforced, although significantly less than in the standard laboratory experiment,and that enforcement is significantly more common in Switzerland than in New York. Moreover, individuals prefer more subtle forms of enforcement to direct punishment. We also find that enforcement is less frequent in littered than in clean contexts, suggesting that broken windows might not only foster deviant behavior but also weaken informal social control. Finally, we find that opportunity structure can encourage people to maintain norms, as indicated by the fact that people are more likely to voluntarily pick up litter when it is closer to a trash bin.

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The low-background, VUV-sensitive 3-inch diameter photomultiplier tube R11410 has been developed by Hamamatsu for dark matter direct detection experiments using liquid xenon as the target material. We present the results from the joint effort between the XENON collaboration and the Hamamatsu company to produce a highly radio-pure photosensor (version R11410-21) for the XENON1T dark matter experiment. After introducing the photosensor and its components, we show the methods and results of the radioactive contamination measurements of the individual materials employed in the photomultiplier production. We then discuss the adopted strategies to reduce the radioactivity of the various PMT versions. Finally, we detail the results from screening 286 tubes with ultra-low background germanium detectors, as well as their implications for the expected electronic and nuclear recoil background of the XENON1T experiment.

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We have designed and built a laboratory facility to investigate the spectro-photometric and morphologic properties of different types of ice-bearing planetary surface analogs and follow their evolution upon exposure to a low pressure and low temperature environment. The results obtained with this experiment are used to verify and improve our interpretations of current optical remote-sensing datasets. They also provide valuable information for the development and operation of future optical instruments. The Simulation Chamber for Imaging the Temporal Evolution of Analogue Samples (SCITEAS) is a small thermal vacuum chamber equipped with a variety of ports and feedthroughs that permit both in-situ and remote characterizations as well as interacting with the sample. A large quartz window located directly above the sample is used to observe its surface from outside with a set of visible and near-infrared cameras. The sample holder can be easily and quickly inserted and removed from the chamber and is compatible with the other measurement facilities of the Laboratory for Outflow Studies of Sublimating Materials (LOSSy) at the University of Bern. We report here on the results of two of the first experiments performed in the SCITEAS chamber. In the first experiment, fine-grained water ice mixed with dark organic and mineral matter was left to sublime in vacuum and at low temperature, simulating the evolution of the surface of a comet nucleus approaching the Sun. We observed and characterized the formation and evolution of a crust of refractory organic and mineral matter at the surface of the sample and linked the evolution of its structure and texture to its spectro-photometric properties. In the second experiment, a frozen soil was prepared by freezing a mixture of smectite mineral and water. The sample was then left to sublime for 6 h to simulate the loss of volatiles from icy soil at high latitudes on Mars. Colour images were produced using the definitions of the filters foreseen for the CaSSIS imager of the Exomars/TGO mission in order to prepare future science operations.

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The etiological role of enterotoxigenic E. coli (ETEC) in diarrheal diseases of man and domestic animals is firmly established. Besides the production of enterotoxins (ST and LT), ETEC produces other important virulence factors; the colonization factor antigens (CFAs). CFAs mediate the attachment of ETEC to the epithelial cells of the small intestine, and this favors colonization by the bacteria and facilitates delivery of the enterotoxins to the intestinal cells.^ The production of enterotoxin and CFA is determined by plasmids and has been found to be restricted to a select number of E. coli serotypes.^ In this work, plasmid DNA analysis was performed in twenty-three CFA/II-producing enterotoxigenic Escherichia coli strains and their spontaneous CFA/II-negative derivatives. In some cases, strains lost the high molecular weight plasmid and also the ability to produce CFA/II, ST and LT. In other cases there was a deletion of the plasmid, which produced strains that were CFA/II('-), ST('-), LT('-) or CFA/II('-), ST('+), LT('+).^ The CFA/II plasmid from strain PB-176 (06:H16:CFA/II('+), ST('+), LT('+)) was transferred by transformation into E. coli K12 with concomitant transfer of the three characteristics: CFA/II, ST and LT.^ A physical map of the prototype CFA/II:ST:LT (pMEP60) plasmid was constructed by restriction endonuclease analysis and compared to plasmids from three other CFA/II-producing strains. A CFA/II-negative (but ST and LT positive) deletion derivative of pMEP60 (pMEP30) was also included in the map. The four CFA/II plasmids analyzed had a common region of approximately 30 kilobase pairs. The toxin genes were approximately 5 kbp apart and about 20 kbp from the common region. The information given by this physical map could be of great value when constructing a clone that will express the CFA/II genes but not the toxin genes. ^

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The 1971 ruling of the California Supreme Court in the case of Serrano v. Priest initiated a chain of events that abruptly ended local financing of public schools in California. In seven short years, California transformed its school finance system from a decentralized one in which local communities chose how much to spend on their schools to a centralized one in which the state legislature determines the expenditures of every school district. This paper begins by describing California's school finance system before Serrano and the transformation from local to state finance. It then delineates some consequences of that transformation and draws lessons from California's experience with school finance reform.

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Margarete Goldstein