2,716 research outputs found

    Performance of the Colorado wind-profiling network, part 1.5A

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    The Wave Propagation Laboratory (WPL) has operated a network of radar wind Profilers in Colorado for about 1 year. The network consists of four VHF (50-MHz) radars and a UHF (915-MHz) radar. The Platteville VHF radar was developed by the Aeronomy Laboratory (AL) and has been operated jointly by WPL and AL for several years. The other radars were installed between February and May 1983. Experiences with these radars and some general aspects of tropospheric wind measurements with Doppler radar are discussed

    Polarization Observables for Two-Pion Production off the Nucleon

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    We develop polarization observables for the processes γN→ππN\gamma N\to\pi\pi N and πN→ππN\pi N\to\pi\pi N, using both a helicity and hybrid helicity-transversity basis. Such observables are crucial if processes that produce final states consisting of a spin-1/2 baryon and two pseudoscalar mesons are to be fully exploited for baryon spectroscopy. We derive relationships among the observables, as well as inequalities that they must satisfy. We also discuss the observables that must be measured in `complete' experiments, and briefly examine the prospects for measurement of some of these observables in the near future.Comment: 20 pages, using revtex

    Eugene Garfield-Remembering-The Passing of a Giant: Eugene Garfield Dies at 90

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    Scalar and vector form factors of the in-medium nucleon

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    Using the quark-meson coupling model, we calculate the form factors at sigma- and omega-nucleon strong-interaction vertices in nuclear matter. The Peierls-Yoccoz projection technique is used to take account of center of mass and recoil corrections. We also apply the Lorentz contraction to the internal quark wave function. The form factors are reduced by the nuclear medium relative to those in vacuum. At normal nuclear matter density and Q^2 = 1 GeV^2, the reduction rate in the scalar form factor is about 15%, which is almost identical to that in the vector one. We parameterize the ratios of the form factors in symmetric nuclear matter to those in vacuum as a function of nuclear density and momentum transfer.Comment: 13 pages, 2 figures, references are up date

    Parameter Estimation and Quantitative Parametric Linkage Analysis with GENEHUNTER-QMOD

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    Objective: We present a parametric method for linkage analysis of quantitative phenotypes. The method provides a test for linkage as well as an estimate of different phenotype parameters. We have implemented our new method in the program GENEHUNTER-QMOD and evaluated its properties by performing simulations. Methods: The phenotype is modeled as a normally distributed variable, with a separate distribution for each genotype. Parameter estimates are obtained by maximizing the LOD score over the normal distribution parameters with a gradient-based optimization called PGRAD method. Results: The PGRAD method has lower power to detect linkage than the variance components analysis (VCA) in case of a normal distribution and small pedigrees. However, it outperforms the VCA and Haseman-Elston regression for extended pedigrees, nonrandomly ascertained data and non-normally distributed phenotypes. Here, the higher power even goes along with conservativeness, while the VCA has an inflated type I error. Parameter estimation tends to underestimate residual variances but performs better for expectation values of the phenotype distributions. Conclusion: With GENEHUNTER-QMOD, a powerful new tool is provided to explicitly model quantitative phenotypes in the context of linkage analysis. It is freely available at http://www.helmholtz-muenchen.de/genepi/downloads. Copyright (C) 2012 S. Karger AG, Base

    Capturing innovation: entrepreneurial activity within an education organisation

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    The 1990's in Victoria saw a political and economical shift away from the social justice themes of previous years to an economic rationalist approach to public sector services. Like other countries, educational reform initiatives focused on the introduction of market-oriented commercial practices. These were characterised by increased accountability for expenditure, pressure to supplement publicly funded income with commercial ventures, rationalisation of staff, privatisation of some services and a business-oriented approach to service provision. As part of this shift TAFE Institutes in Victoria were actively encouraged to embark on a business-based, entrepreneurial approach to training delivery in a competitive, user-choice market. This changing external environment is the context for this 'practitioner research' investigative project - the development of a motorsports program as a case study of innovation and entrepreneurship at Wodonga Institute of TAFE. A participant-observer research approach was applied to examine the perceptions of the stakeholders about the development of the program. Data was collected through semi-formal interviews with stakeholders, maintaining a reflective research journal and reviewing related literature. Analysis of the data identified emergent themes (enabling factors and barriers), reflecting at a micro level, similar themes and issues from current research and debate at national level. The themes are similarly reflected in literature on innovation, organisational change and entrepreneurship. The products generated from the investigative research project are: * Capturing Innovation: Entrepreneurial Activity Within a Publicly Funded Educational Organisation, an exegesis examining innovation and entrepreneurship at Wodonga Institute of TAFE through a case study (the motorsports program) * What a Great Idea! Where to From Here?, a set of guidelines for Wodonga Institute of TAFE practitioners about what is required in presenting their ideas to Senior Management (Appendix 1 and Appendix 2), and * a Professional development workshop agenda to support promotion of the guidelines (Appendix 2) * recommendations to Wodonga Institute of TAFE Directorate (Director/CEO and two Deputy Directors) for supporting the development of innovative ideas (Chapter 6). These outcomes aim to increase the success rate of innovative ideas being captured and developed into training programs and products at Wodonga Institute of TAFE

    Strong-field effects in the Rabi oscillations of the superconducting phase qubit

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    Rabi oscillations have been observed in many superconducting devices, and represent prototypical logic operations for quantum bits (qubits) in a quantum computer. We use a three-level multiphoton analysis to understand the behavior of the superconducting phase qubit (current-biased Josephson junction) at high microwave drive power. Analytical and numerical results for the ac Stark shift, single-photon Rabi frequency, and two-photon Rabi frequency are compared to measurements made on a dc SQUID phase qubit with Nb/AlOx/Nb tunnel junctions. Good agreement is found between theory and experiment.Comment: 4 pages, 4 figures, accepted for publication in IEEE Trans. Appl. Supercon

    The trans-activation domain of the sporulation response regulator Spo0A revealed by X-ray crystallography

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    Sporulation in Bacillus involves the induction of scores of genes in a temporally and spatially co-ordinated programme of cell development. Its initiation is under the control of an expanded two-component signal transduction system termed a phosphorelay. The master control element in the decision to sporulate is the response regulator, Spo0A, which comprises a receiver or phosphoacceptor domain and an effector or transcription activation domain. The receiver domain of Spo0A shares sequence similarity with numerous response regulators, and its structure has been determined in phosphorylated and unphosphorylated forms. However, the effector domain (C-Spo0A) has no detectable sequence similarity to any other protein, and this lack of structural information is an obstacle to understanding how DNA binding and transcription activation are controlled by phosphorylation in Spo0A. Here, we report the crystal structure of C-Spo0A from Bacillus stearothermophilus revealing a single alpha -helical domain comprising six alpha -helices in an unprecedented fold. The structure contains a helix-turn-helix as part of a three alpha -helical bundle reminiscent of the catabolite gene activator protein (CAP), suggesting a mechanism for DNA binding. The residues implicated in forming the sigma (A)-activating region clearly cluster in a flexible segment of the polypeptide on the opposite side of the structure from that predicted to interact with DNA. The structural results are discussed in the context of the rich array of existing mutational data

    What is a War Crime?

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    What is a war crime? The question appears to have a simple answer: a war crime is a violation of the law of war. But do all violations of the law of war qualify as war crimes? And are all war crimes violations of the law of war? These questions are not new. In 1942, Hersch Lauterpacht, a leading international lawyer who assisted the prosecution of the Nazis for war crimes at the International Military Tribunal (IMT) in Nuremberg, wrote a memo in which he asked, “Is there a definition of war crimes?” More than seven decades later, the answer to his question remains unsettled
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