3,110 research outputs found
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Taking the paper out of news: A case study of Taloussanomat, Europe's first online-only newspaper
Using in-depth interviews, newsroom observation, and internal documents, this case study presents and analyses changes that have taken place at Finnish financial daily Taloussanomat since it stopped printing on 28 December 2007 to focus exclusively on digital delivery via the Web, email, and mobile. It reveals the savings that can be achieved when a newspaper no longer prints and distributes a physical product; but also the revenue lost from subscriptions and print advertising. The consequences of a newspaper's decision to go online-only are examined as they relate to its business model, website traffic, and editorial practice. The findings illustrate the extent to which the medium rather than the content it carries determines news consumption patterns, show the differing attention a newspaper and its online substitute command, and reveal the changes to working patterns journalists can expect in the online-only environment
Application of high-precision two-way ranging to Galileo Earth-1 encounter navigation
The application of precision two-way ranging to orbit determination with relatively short data arcs is investigated for the Galileo spacecraft's approach to its first Earth encounter (December 8, 1990). Analysis of previous S-band (2.3-GHz) ranging data acquired from Galileo indicated that under good signal conditions submeter precision and 10-m ranging accuracy were achieved. It is shown that ranging data of sufficient accuracy, when acquired from multiple stations, can sense the geocentric angular position of a distant spacecraft. A range data filtering technique, in which explicit modeling of range measurement bias parameters for each station pass is utilized, is shown to largely remove the systematic ground system calibration errors and transmission media effects from the Galileo range measurements, which would otherwise corrupt the angle-finding capabilities of the data. The accuracy of the Galileo orbit solutions obtained with S-band Doppler and precision ranging were found to be consistent with simple theoretical calculations, which predicted that angular accuracies of 0.26-0.34 microrad were achievable. In addition, the navigation accuracy achieved with precision ranging was marginally better than that obtained using delta-differenced one-way range (delta DOR), the principal data type that was previously used to obtain spacecraft angular position measurements operationally
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On Digital Distribution’s Failure to Solve Newspapers’ Existential Crisis: Symptoms, Causes, Consequences and Remedies
This chapter examines some of the symptoms and causes of the crisis facing newspapers via analyses of their finances and of audience measures. The consequences of the crisis, and whether there are any realistic remedies, are also considered, both in relation to journalism as a product and to the institutions, such as newspapers, that have traditionally produced it. We start with an analysis of the financial performance of multiplatform news publishers in Australia, Europe and the USA, which leads us to conclude that digital distribution is not reversing newspapers’ decline, and raises questions about the support for journalism in the long term. Next, some of the consequences of the declines that have already taken place are discussed. Moving from consequences to possible remedies, the chapter focuses on two areas. Firstly, media policy, and secondly, journalism as a product: what news should be produced and how it should be delivered. Another strand of the chapter concerns audience measures. They are used to help explain newspapers’ continuing dependency on print revenues, and are understood, depending on their constitution and use, as both a party to the crisis and as an able assistant in its alleviation
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Multi-line Adaptive Perimetry (MAP): A New Procedure for Quantifying Visual Field Integrity for Rapid Assessment of Macular Diseases.
PurposeIn order to monitor visual defects associated with macular degeneration (MD), we present a new psychophysical assessment called multiline adaptive perimetry (MAP) that measures visual field integrity by simultaneously estimating regions associated with perceptual distortions (metamorphopsia) and visual sensitivity loss (scotoma).MethodsWe first ran simulations of MAP with a computerized model of a human observer to determine optimal test design characteristics. In experiment 1, predictions of the model were assessed by simulating metamorphopsia with an eye-tracking device with 20 healthy vision participants. In experiment 2, eight patients (16 eyes) with macular disease completed two MAP assessments separated by about 12 weeks, while a subset (10 eyes) also completed repeated Macular Integrity Assessment (MAIA) microperimetry and Amsler grid exams.ResultsResults revealed strong repeatability of MAP and high accuracy, sensitivity, and specificity (0.89, 0.81, and 0.90, respectively) in classifying patient eyes with severe visual impairment. We also found a significant relationship in terms of the spatial patterns of performance across visual field loci derived from MAP and MAIA microperimetry. However, there was a lack of correspondence between MAP and subjective Amsler grid reports in isolating perceptually distorted regions.ConclusionsThese results highlight the validity and efficacy of MAP in producing quantitative maps of visual field disturbances, including simultaneous mapping of metamorphopsia and sensitivity impairment.Translational relevanceFuture work will be needed to assess applicability of this examination for potential early detection of MD symptoms and/or portable assessment on a home device or computer
Complement-mediated kidney diseases
It has long been known that the complement cascade is activated in various forms of glomerulonephritis. In many of these diseases, immune-complexes deposit in the glomeruli and activate the classical pathway. Researchers have also identified additional mechanisms by which complement is activated in the kidney, including diseases in which the alternative and lectin pathways are activated. The kidney appears to be particularly susceptible to activation of the alternative pathway, and this pathway has been implicated as a primary driver of atypical hemolytic uremic syndrome, C3 glomerulopathy, anti-neutrophil cytoplasmic antibody-associated vasculitis, as well as some forms of immune-complex glomerulonephritis. In this paper we review the shared and distinct mechanisms by which complement is activated in these different diseases. We also review the opportunities for using therapeutic complement inhibitors to treat kidney diseases
Predicting individual contrast sensitivity functions from acuity and letter contrast sensitivity measurements.
Contrast sensitivity (CS) is widely used as a measure of visual function in both basic research and clinical evaluation. There is conflicting evidence on the extent to which measuring the full contrast sensitivity function (CSF) offers more functionally relevant information than a single measurement from an optotype CS test, such as the Pelli-Robson chart. Here we examine the relationship between functional CSF parameters and other measures of visual function, and establish a framework for predicting individual CSFs with effectively a zero-parameter model that shifts a standard-shaped template CSF horizontally and vertically according to independent measurements of high contrast acuity and letter CS, respectively. This method was evaluated for three different CSF tests: a chart test (CSV-1000), a computerized sine-wave test (M&S Sine Test), and a recently developed adaptive test (quick CSF). Subjects were 43 individuals with healthy vision or impairment too mild to be considered low vision (acuity range of -0.3 to 0.34 logMAR). While each test demands a slightly different normative template, results show that individual subject CSFs can be predicted with roughly the same precision as test-retest repeatability, confirming that individuals predominantly differ in terms of peak CS and peak spatial frequency. In fact, these parameters were sufficiently related to empirical measurements of acuity and letter CS to permit accurate estimation of the entire CSF of any individual with a deterministic model (zero free parameters). These results demonstrate that in many cases, measuring the full CSF may provide little additional information beyond letter acuity and contrast sensitivity
Bifurcations in nonlinear models of fluid-conveying pipes supported at both ends
Stationary bifurcations in several nonlinear models of fluid conveying pipes
fixed at both ends are analyzed with the use of Lyapunov-Schmidt reduction and
singularity theory. Influence of gravitational force, curvature and vertical
elastic support on various properties of bifurcating solutions are
investigated. In particular the conditions for occurrence of supercritical and
subcritical bifurcations are presented for the models of Holmes, Thurman and
Mote, and Paidoussis.Comment: to appear in Journal of Fluids and Structures; 6 figure
Preschool planning guide (1993)
"11/1993.""This MU publication replaces a discontinued publication by the same title and series number.
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