4,031 research outputs found

    Universal power law behaviors in genomic sequences and evolutionary models

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    We study the length distribution of a particular class of DNA sequences known as 5'UTR exons. These exons belong to the messanger RNA of protein coding genes, but they are not coding (they are located upstream of the coding portion of the mRNA) and are thus less constrained from an evolutionary point of view. We show that both in mouse and in human these exons show a very clean power law decay in their length distribution and suggest a simple evolutionary model which may explain this finding. We conjecture that this power law behaviour could indeed be a general feature of higher eukaryotes.Comment: 15 pages, 3 figure

    Asymptotic Level Density of the Elastic Net Self-Organizing Feature Map

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    Whileas the Kohonen Self Organizing Map shows an asymptotic level density following a power law with a magnification exponent 2/3, it would be desired to have an exponent 1 in order to provide optimal mapping in the sense of information theory. In this paper, we study analytically and numerically the magnification behaviour of the Elastic Net algorithm as a model for self-organizing feature maps. In contrast to the Kohonen map the Elastic Net shows no power law, but for onedimensional maps nevertheless the density follows an universal magnification law, i.e. depends on the local stimulus density only and is independent on position and decouples from the stimulus density at other positions.Comment: 8 pages, 10 figures. Link to publisher under http://link.springer.de/link/service/series/0558/bibs/2415/24150939.ht

    Culture of Intimidation: Power Relationships, Quiescence, and Rebellion in Oak Ridge, Tennessee

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    Studies suggest that quiescence, or the absence of challenge from deprived groups can be explained as a function of power relationships. Power has the potential to influence the decision-making process by monopolizing decision-making arenas. Furthermore, elites that occupy positions of power have the capability to resist challenges from deprived groups by preventing certain issues or grievances from ever being raised. This study’s focus is a former nuclear weapons production facility (the former K-25 Gaseous Diffusion Plant) in Oak Ridge, Tennessee, the quiescent nature of workers there, and the subsequent rise of rebellion. I employ a historical perspective using in-depth interviews and secondary data sources to investigate the perceptions of workers on power relationships. I explore the consequences of unequal power relationships on workers. K-25 was the first site built for the Manhattan Project in 1943. Findings indicate that the quiescent nature of K-25 workers cannot be explained by worker apathy or consensus with the status quo. In fact, the perception of quiescence can be explained by power relationships between dominant and subordinate groups. Generalized grievances were present, but were controlled and contained by the Department of Energy (DOE) and its corporate contractors. Even as rebellion emerged, traces of quiescence can still be found among workers in Oak Ridge

    Capacitive pressure transducer system

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    Closed loop capacitive pressure transducer with extended frequency response for very low pressure measurement

    Symposium: The 19th Amendment at 100: Citizen Soldiers and the Foundational Fusion of Masculinity, Citizenship, and Military Service

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    The Akron Law School’s conference on the 100th anniversary of the passage of the Nineteenth Amendment offered the chance to fight the eulogization of the Nineteenth Amendment and explore its modern relevance. This paper concludes that the Nineteenth Amendment cannot be understood without connecting it to broader conceptions of citizenship, masculinities, and military service, thus revealing its ongoing relevance to military inclusion and integration

    A Solvable Sequence Evolution Model and Genomic Correlations

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    We study a minimal model for genome evolution whose elementary processes are single site mutation, duplication and deletion of sequence regions and insertion of random segments. These processes are found to generate long-range correlations in the composition of letters as long as the sequence length is growing, i.e., the combined rates of duplications and insertions are higher than the deletion rate. For constant sequence length, on the other hand, all initial correlations decay exponentially. These results are obtained analytically and by simulations. They are compared with the long-range correlations observed in genomic DNA, and the implications for genome evolution are discussed.Comment: 4 pages, 4 figure

    Parameter estimation in pair hidden Markov models

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    This paper deals with parameter estimation in pair hidden Markov models (pair-HMMs). We first provide a rigorous formalism for these models and discuss possible definitions of likelihoods. The model being biologically motivated, some restrictions with respect to the full parameter space naturally occur. Existence of two different Information divergence rates is established and divergence property (namely positivity at values different from the true one) is shown under additional assumptions. This yields consistency for the parameter in parametrization schemes for which the divergence property holds. Simulations illustrate different cases which are not covered by our results.Comment: corrected typo

    Local Government Law

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    Spontaneous dressed-state polarization in the strong driving regime of cavity QED

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    We utilize high-bandwidth phase quadrature homodyne measurement of the light transmitted through a Fabry-Perot cavity, driven strongly and on resonance, to detect excess phase noise induced by a single intracavity atom. We analyze the correlation properties and driving-strength dependence of the atom-induced phase noise to establish that it corresponds to the long-predicted phenomenon of spontaneous dressed-state polarization. Our experiment thus provides a demonstration of cavity quantum electrodynamics in the strong driving regime, in which one atom interacts strongly with a many-photon cavity field to produce novel quantum stochastic behavior.Comment: 4 pages, 4 color figure
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