13 research outputs found

    A single sensor controls large variations in zinc quotas in a marine cyanobacterium

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    Marine cyanobacteria are critical players in global nutrient cycles that crucially depend on trace metals in metalloenzymes, including zinc for CO2 fixation and phosphorus acquisition. How strains proliferating in the vast oligotrophic ocean gyres thrive at ultra-low zinc concentrations is currently unknown. Using Synechococcus sp. WH8102 as a model we show that its zinc-sensor protein Zur differs from all other known bacterial Zur proteins in overall structure and the location of its sensory zinc site. Uniquely, Synechococcus Zur activates metallothionein gene expression, which supports cellular zinc quotas spanning two orders of magnitude. Thus, a single zinc sensor facilitates growth across pico- to micromolar zinc concentrations with the bonus of banking this precious resource. The resultant ability to grow well at both ultra-low and excess zinc, together with overall lower zinc requirements, likely contribute to the broad ecological distribution of Synechococcus across the global oceans

    How Verifiable Cheap-Talk Can Communicate Unverifiable Information

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    This study describes a “cheap-talk” model in which sellers can credibly convey unverifiable information by choosing whether or not to exaggerate verifiable information. We find that unexaggerated claims can communicate favorable unverifiable information if buyers are not too likely to verify claims, and sellers with better information care more about future prices than sellers with worse information. However, there is always another equilibrium in which sellers exaggerate all verifiable claims. Laboratory tests show that when buyers infrequently verify the sellers' claims, players converge to the equilibria close to the example provided in instructions. When buyers are very likely to verify claims, players fail to converge to any equilibrium. Both of these results are consistent with an evolutionary learning model, but inconsistent with the intuitive criteria of Cho and Kreps (1987). We discuss the implications of our results for both consumer and financial markets. Copyright Springer Science + Business Media, Inc. 2005cheap talk, evolutionary game theory, signaling, quality, earnings management, disclosure,

    International primate neuroscience research regulation, public engagement and transparency opportunities

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    Scientific excellence is a necessity for progress in biomedical research. As research becomes ever more international, establishing international collaborations will be key to advancing our scientific knowledge. Understanding the similarities in standards applied by different nations to animal research, and where the differences might lie, is crucial. Cultural differences and societal values will also contribute to these similarities and differences between countries and continents. Our overview is not comprehensive for all species, but rather focuses on non-human primate (NHP) research, involving New World marmosets and Old World macaques, conducted in countries where NHPs are involved in neuroimaging research. Here, an overview of the ethics and regulations is provided to help assess welfare standards amongst primate research institutions. A comparative examination of these standards was conducted to provide a basis for establishing a common set of standards for animal welfare. These criteria may serve to develop international guidelines, which can be managed by an International Animal Welfare and Use Committee (IAWUC). Internationally, scientists have a moral responsibility to ensure excellent care and welfare of their animals, which in turn, influences the quality of their research. When working with animal models, maintaining a high quality of care (“culture of care”) and welfare is essential. The transparent promotion of this level of care and welfare, along with the results of the research and its impact, may reduce public concerns associated with animal experiments in neuroscience research
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