22,399 research outputs found

    Survey of Australian father\u27s attitudes towards infant vaccination: Findings from the Australian Father\u27s Study

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    Objective: To investigate the attitudes of expectant Australian fathers towards vaccination, and to identify factors which may influence these attitudes. Methods: A cross-sectional survey study of 407 Australian men with expectant partners, mean age 30.4 (SD 6.7). Self reported attitude, level of knowledge and information resources accessed regarding pregnancy related issues. Participant demographics collected included: Age, number of children, relationship status, level of education, employment information and smoking status. Results: Majority (89%) of participants had a positive attitude towards infant vaccination, 9% felt neutral and 2% had negative attitudes. Positive attitudes towards vaccination were associated with lower self-reported knowledge of pregnancy issues but a higher likelihood of discussing pregnancy issues with health care providers rather than sourcing information from the internet (both p\u3c0.001). Conclusion: A majority of Australian expectant fathers have a positive attitude towards infant vaccination. Fathers with negative attitudes to vaccination self-reported higher levels of knowledge. They were more likely to obtain information from the Internet instead of healthcare staff. Implication for public health: Including fathers in health discussion with knowledgeable health care providers may result in increased vaccine uptake

    A Reciprocity Theorem for Monomer-Dimer Coverings

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    The problem of counting monomer-dimer coverings of a lattice is a longstanding problem in statistical mechanics. It has only been exactly solved for the special case of dimer coverings in two dimensions. In earlier work, Stanley proved a reciprocity principle governing the number N(m,n)N(m,n) of dimer coverings of an mm by nn rectangular grid (also known as perfect matchings), where mm is fixed and nn is allowed to vary. As reinterpreted by Propp, Stanley's result concerns the unique way of extending N(m,n)N(m,n) to n<0n < 0 so that the resulting bi-infinite sequence, N(m,n)N(m,n) for n∈Zn \in {Z}, satisfies a linear recurrence relation with constant coefficients. In particular, Stanley shows that N(m,n)N(m,n) is always an integer satisfying the relation N(m,−2−n)=ϵm,nN(m,n)N(m,-2-n) = \epsilon_{m,n}N(m,n) where ϵm,n=1\epsilon_{m,n} = 1 unless m≡m\equiv 2(mod 4) and nn is odd, in which case ϵm,n=−1\epsilon_{m,n} = -1. Furthermore, Propp's method is applicable to higher-dimensional cases. This paper discusses similar investigations of the numbers M(m,n)M(m,n), of monomer-dimer coverings, or equivalently (not necessarily perfect) matchings of an mm by nn rectangular grid. We show that for each fixed mm there is a unique way of extending M(m,n)M(m,n) to n<0n < 0 so that the resulting bi-infinite sequence, M(m,n)M(m,n) for n∈Zn \in {Z}, satisfies a linear recurrence relation with constant coefficients. We show that M(m,n)M(m,n), a priori a rational number, is always an integer, using a generalization of the combinatorial model offered by Propp. Lastly, we give a new statement of reciprocity in terms of multivariate generating functions from which Stanley's result follows.Comment: 13 pages, 12 figures, to appear in the proceedings of the Discrete Models for Complex Systems (DMCS) 2003 conference. (v2 - some minor changes

    Turbojet blade vibration data acquisition design and feasibility testing

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    A turbojet blade vibration data acquisition system was designed to allow the measurement of blade vibration. The data acquisition system utilizing 96 microprocessors to gather data from optical probes, store, sort and transmit to the central computer is described. Areas of high technical risk were identified and a two-microprocessor system was breadboarded and tested to investigate these areas. Results show that the system was feasible and that low technical risk would be involved in proceeding with the complete system fabrication

    Evaluation of a vertical laminar flow biological safety cabinet

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    Vertical laminar flow biological safety cabinet to protect personnel against microbial contaminatio

    Recovery of Viable Microorganisms from Solids. I - Model Systems

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    Solidification process for recovering viable microorganisms to aid spacecraft sterilization procedure

    Methods for measuring the citations and productivity of scientists across time and discipline

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    Publication statistics are ubiquitous in the ratings of scientific achievement, with citation counts and paper tallies factoring into an individual's consideration for postdoctoral positions, junior faculty, tenure, and even visa status for international scientists. Citation statistics are designed to quantify individual career achievement, both at the level of a single publication, and over an individual's entire career. While some academic careers are defined by a few significant papers (possibly out of many), other academic careers are defined by the cumulative contribution made by the author's publications to the body of science. Several metrics have been formulated to quantify an individual's publication career, yet none of these metrics account for the dependence of citation counts and journal size on time. In this paper, we normalize publication metrics across both time and discipline in order to achieve a universal framework for analyzing and comparing scientific achievement. We study the publication careers of individual authors over the 50-year period 1958-2008 within six high-impact journals: CELL, the New England Journal of Medicine (NEJM), Nature, the Proceedings of the National Academy of Science (PNAS), Physical Review Letters (PRL), and Science. In comparing the achievement of authors within each journal, we uncover quantifiable statistical regularity in the probability density function (pdf) of scientific achievement across both time and discipline. The universal distribution of career success within these arenas for publication raises the possibility that a fundamental driving force underlying scientific achievement is the competitive nature of scientific advancement.Comment: 25 pages in 1 Column Preprint format, 7 Figures, 4 Tables. Version II: changes made in response to referee comments. Note: change in definition of "Paper shares.

    A generic cyclic theorem prover

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    We describe the design and implementation of an automated theorem prover realising a fully general notion of cyclic proof. Our tool, called CYCLIST, is able to construct proofs obeying a very general cycle scheme in which leaves may be linked to any other matching node in the proof, and to verify the general, global infinitary condition on such proof objects ensuring their soundness. CYCLIST is based on a new, generic theory of cyclic proofs that can be instantiated to a wide variety of logics. We have developed three such concrete instantiations, based on: (a) first-order logic with inductive definitions; (b) entailments of pure separation logic; and (c) Hoare-style termination proofs for pointer programs. Experiments run on these instantiations indicate that CYCLIST offers significant potential as a future platform for inductive theorem proving. © Springer-Verlag Berlin Heidelberg 2012

    Ultrafast Resonant Polarization Interferometry: Towards the First Direct Detection of Vacuum Polarization

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    Vacuum polarization, an effect predicted nearly 70 years ago, is still yet to be directly detected despite significant experimental effort. Previous attempts have made use of large liquid-helium cooled electromagnets which inadvertently generate spurious signals that mask the desired signal. We present a novel approach for the ultra-sensitive detection of optical birefringence that can be usefully applied to a laboratory detection of vacuum polarization. The new technique has a predicted birefringence measurement sensitivity of Δn∼1020\Delta n \sim 10^{20} in a 1 second measurement. When combined with the extreme polarizing fields achievable in this design we predict that a vacuum polarization signal will be seen in a measurement of just a few days in duration.Comment: 9 pages, 2 figures. submitted to PR
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