9 research outputs found

    On the String Consensus Problem and the Manhattan Sequence Consensus Problem

    Full text link
    In the Manhattan Sequence Consensus problem (MSC problem) we are given kk integer sequences, each of length ll, and we are to find an integer sequence xx of length ll (called a consensus sequence), such that the maximum Manhattan distance of xx from each of the input sequences is minimized. For binary sequences Manhattan distance coincides with Hamming distance, hence in this case the string consensus problem (also called string center problem or closest string problem) is a special case of MSC. Our main result is a practically efficient O(l)O(l)-time algorithm solving MSC for k5k\le 5 sequences. Practicality of our algorithms has been verified experimentally. It improves upon the quadratic algorithm by Amir et al.\ (SPIRE 2012) for string consensus problem for k=5k=5 binary strings. Similarly as in Amir's algorithm we use a column-based framework. We replace the implied general integer linear programming by its easy special cases, due to combinatorial properties of the MSC for k5k\le 5. We also show that for a general parameter kk any instance can be reduced in linear time to a kernel of size k!k!, so the problem is fixed-parameter tractable. Nevertheless, for k4k\ge 4 this is still too large for any naive solution to be feasible in practice.Comment: accepted to SPIRE 201

    Size Doesn't Matter: Towards a More Inclusive Philosophy of Biology

    Get PDF
    notes: As the primary author, O’Malley drafted the paper, and gathered and analysed data (scientific papers and talks). Conceptual analysis was conducted by both authors.publication-status: Publishedtypes: ArticlePhilosophers of biology, along with everyone else, generally perceive life to fall into two broad categories, the microbes and macrobes, and then pay most of their attention to the latter. ‘Macrobe’ is the word we propose for larger life forms, and we use it as part of an argument for microbial equality. We suggest that taking more notice of microbes – the dominant life form on the planet, both now and throughout evolutionary history – will transform some of the philosophy of biology’s standard ideas on ontology, evolution, taxonomy and biodiversity. We set out a number of recent developments in microbiology – including biofilm formation, chemotaxis, quorum sensing and gene transfer – that highlight microbial capacities for cooperation and communication and break down conventional thinking that microbes are solely or primarily single-celled organisms. These insights also bring new perspectives to the levels of selection debate, as well as to discussions of the evolution and nature of multicellularity, and to neo-Darwinian understandings of evolutionary mechanisms. We show how these revisions lead to further complications for microbial classification and the philosophies of systematics and biodiversity. Incorporating microbial insights into the philosophy of biology will challenge many of its assumptions, but also give greater scope and depth to its investigations

    The outcome-prediction strategy in cases denied certiorari by the U.S. Supreme Court

    No full text
    We investigate whether the substantial use of the outcome-prediction strategy by Supreme Court justices occurs in the petitions denied certiorari by the Court. We show with a computer simulation that [Caldeira, G.A., Wright, J.R., & Zorn, C.J.W. (1999). Journal of Law, Economics and Organization, 15, 549–572], who modeled the missing final votes for denied petitions in order to include them in their study of the use of the outcome-prediction strategy, may have obtained spurious results. Application of the logic of conditional probabilities to the denied petitions suggests that all but those denied by the narrowest of margins are probably considered unacceptable by the justices on non-outcome-oriented grounds, and, therefore, are not subject to use of this strategy. We evaluate the pursuit of the outcome-prediction strategy in petitions that narrowly fail to be granted cert by focusing upon the petitions that are narrowly granted cert and find limited use of the strategy. We conclude that the outcome-prediction strategy probably is little used by the justices in confronting the petitions denied cert and that investigations of the use of this strategy are best confined to those petitions granted cert. Copyright Springer Science + Business Media B.V. 2007U.S. Supreme Court, Certiorari, Strategic behavior, Attitudinal model, Rational choice, Selection bias,

    Accurate rotational constants for linear interstellar carbon chains: achieving experimental accuracy

    No full text

    Altered Apoptosis in AML

    No full text

    Lasers

    No full text

    Assessing written work by determining competence to achieve the module-specific learning outcomes.

    No full text
    This chapter describes lasers and other sources of coherent light that operate in a wide wavelength range. First, the general principles for the generation of coherent continuous-wave and pulsed radiation are treated including the interaction of radiation with matter, the properties of optical resonators and their modes as well as such processes as Q-switching and mode-locking. The general introduction is followed by sections on numerous types of lasers, the emphasis being on todayʼs most important sources of coherent light, in particular on solid-state lasers and several types of gas lasers. An important part of the chapter is devoted to the generation of coherent radiation by nonlinear processes with optical parametric oscillators, difference- and sum-frequency generation, and high-order harmonics. Radiation in the extended ultraviolet (EUV) and x-ray ranges can be generated by free electron lasers (FEL) and advanced x-ray sources. Ultrahigh light intensities up to 1021 W/cm2 open the door to studies of relativistic laser–matter interaction and laser particle acceleration. The chapter closes with a section on laser stabilization

    Tactile reception and behavior of fish

    No full text
    corecore