9,101 research outputs found

    Changes in lipophorins are related to the activation of phenoloxidase in the haemolymph of Locusta migratoria in response to injection of immunogens

    Get PDF
    In Locusta migratoria, activation of phenoloxidase in the haemolymph in response to injection of laminarin is age-dependent: being absent in fifth instar nymphs and newly emerged adults, and only becoming evident four days after the final moult. This pattern of change in phenoloxidase activation correlates with the pattern of change in the concentration of apolipophorin-III (apoLp-III) in the haemolymph. Injection of a conspecific adipokinetic hormone (Lom-AKH-I) has no effect on the phenoloxidase response in nymphs or newly emerged adults but, in adults older than four days, co-injection of the hormone with laminarin prolongs the activation of phenoloxidase in the haemolymph: a similar enhancement of the response to laminarin is observed in locusts that have been starved for 48 h but not injected with AKH-I. During most of the fifth stadium, injection of laminarin results in a decrease in the level of prophenoloxidase in the haemolymph; an effect that is not observed in adults of any age. Marked changes in the concentration of apoLp-III, and the formation of LDLp in the haemolymph, are observed after injection of laminarin (or LPS) and these are remarkably similar, at least qualitatively, to those that occur after injection of AKH-I. The involvement of lipophorins in the activation of locust prophenoloxidase in response to immunogens is discussed

    A social psychological study of ethnonyms: Cognitive representation of the ingroup and intergroup hostility

    Get PDF
    Ethnonyms (M. G. Levin & L. P. Potapov, 1964; from the Greek roots meaning "a national group" and "name") are the names an in-group uses to distinguish itself from out-groups. There has been no social psychological research to date exploring the effects of ethnonyms. The authors report the results of 3 studies examining the potential effects of various features of ethnonyms on intergroup behavior. Analyses of archival data indicate that among indigenous African cultures (Study 1), indigenous Native American cultures (Study 2), and African Americans (Study 3), intergroup hostility was greater among in-groups characterized by less complex ethnonyms. Discussion considers the implications of these results and suggests new directions for research in the social psychological study of ethnonyms

    Waveguide physical modeling of vocal tract acoustics: flexible formant bandwidth control from increased model dimensionality

    Get PDF
    Digital waveguide physical modeling is often used as an efficient representation of acoustical resonators such as the human vocal tract. Building on the basic one-dimensional (1-D) Kelly-Lochbaum tract model, various speech synthesis techniques demonstrate improvements to the wave scattering mechanisms in order to better approximate wave propagation in the complex vocal system. Some of these techniques are discussed in this paper, with particular reference to an alternative approach in the form of a two-dimensional waveguide mesh model. Emphasis is placed on its ability to produce vowel spectra similar to that which would be present in natural speech, and how it improves upon the 1-D model. Tract area function is accommodated as model width, rather than translated into acoustic impedance, and as such offers extra control as an additional bounding limit to the model. Results show that the two-dimensional (2-D) model introduces approximately linear control over formant bandwidths leading to attainable realistic values across a range of vowels. Similarly, the 2-D model allows for application of theoretical reflection values within the tract, which when applied to the 1-D model result in small formant bandwidths, and, hence, unnatural sounding synthesized vowels

    Analysis of the transient behavior of rubbing components

    Get PDF
    Finite element equations are developed for studying deformations and temperatures resulting from frictional heating in sliding system. The formulation is done for linear steady state motion in two dimensions. The equations include the effect of the velocity on the moving components. This gives spurious oscillations in their solutions by Galerkin finite element methods. A method called streamline upwind scheme is used to try to deal with this deficiency. The finite element program is then used to investigate the friction of heating in gas path seal

    Real-time dynamic articulations in the 2-D waveguide mesh vocal tract model

    Get PDF
    Time domain articulatory vocal tract modeling in one-dimensional (1-D) is well established. Previous studies into two-dimensional (2-D) simulation of wave propagation in the vocal tract have shown it to present accurate static vowel synthesis. However, little has been done to demonstrate how such a model might accommodate the dynamic tract shape changes necessary in modeling speech. Two methods of applying the area function to the 2-D digital waveguide mesh vocal tract model are presented here. First, a method based on mapping the cross-sectional area onto the number of waveguides across the mesh, termed a widthwise mapping approach is detailed. Discontinuity problems associated with the dynamic manipulation of the model are highlighted. Second, a new method is examined that uses a static-shaped rectangular mesh with the area function translated into an impedance map which is then applied to each waveguide. Two approaches for constructing such a map are demonstrated; one using a linear impedance increase to model a constriction to the tract and another using a raised cosine function. Recommendations are made towards the use of the cosine method as it allows for a wider central propagational channel. It is also shown that this impedance mapping approach allows for stable dynamic shape changes and also permits a reduction in sampling frequency leading to real-time interaction with the model

    An Introduction to the 'Special Volume Spectroscopy and Chemometrics in R'

    Get PDF
    This special volume collates ten issues under the rubric "Spectroscopy and Chemometrics in R". In so doing, it provides an overview of the breadth, depth and state of the art of R-based software projects for spectroscopy and chemometrics applications. Just as the authors have contributed to R their documentation and source code, so has R contributed to the quality, standardization and dissemination of their software, as this volume attests. We hope that the volume is inspiring to both computational statisticians interested in applications of their methodologies and to spectroscopists or chemometricians in need of solutions to their data analysis problems.

    Benchmarking Utility Clean Energy Deployment: 2014

    Get PDF
    This report assembles data from more than 10 sources, including state Renewable Portfolio Standard (RPS) annual reports, U.S. Securities and Exchange Commission 10-K filings and Public Utility Commission reports, to show how 32 of the largest U.S. investor-owned electric utility holding companies stack up on renewable energy and energy efficiency

    An Evaluation of the Economic, Environmental and Social Impacts of NSW DPI Investments in IPM Research in Invertebrate Rice Pests

    Get PDF
    Research into IPM technologies has been conducted by NSW DPI for over 20 years. Evaluating the returns from investment in specific research and development projects is an important component of the NSW DPI science and research program. An economic evaluation has been conducted of IPM in managing invertebrate pests in rice in NSW. We found that there has been widespread adoption of many IPM practices amongst NSW rice growers leading to a flow of economic benefits to the rice industry and the community. Important environmental and human health benefits were also identified. A benefit-cost ratio of 9.05 was calculated for the return to NSW DPI investment in rice invertebrate pests IPM research. The net present value of the benefits of this research to 2020 was $67.9 million. Important environmental and human health benefits were not valued nor were ‘spillover’ benefits to other States.benefit cost analysis, rice, IPM, invertebrate pests, evaluation, Crop Production/Industries, Environmental Economics and Policy, Farm Management, Production Economics, Q160,

    Trends in Research, Productivity Growth and Competitiveness in Agriculture in New Zealand and Australia

    Get PDF
    Investment in R&D has long been regarded as an important source of productivity growth in New Zealand and Australian agriculture. Perhaps because research lags are long, current investment in R&D is monitored closely. In this paper trends in public investment in R&D and in productivity growth are reviewed. Investment in R&D has been flat in both countries although in recent years investment in New Zealand has increased. Nevertheless research intensity in Australia has been significantly higher than that in New Zealand. Productivity growth is also likely to have been higher. Econometric evidence about the sources of productivity growth is rarely clear. We develop some scenarios about the importance of domestic and foreign R&D and other sources of productivity growth and find that returns to investments in domestic research in both countries are likely to have been in the order of 15-20 percent.Productivity, research and development, research evaluation, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies,
    corecore