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201.
Valuing the Arts: A Contingent Valuation Approach   总被引:5,自引:3,他引:2  
Government funding of the arts has received considerable attention in the United States in recent years. Efforts to cut funding to the National Endowment for the Arts and declining budgets for state arts agencies have raised questions about how much individuals value the arts. This paper applies the contingent valuation method to assess this value, using surveys of random households and of arts patrons. Our analysis estimated a mean willingness to pay (WTP) among all Kentucky households from $6 to$27, depending on the estimation technique used and on whether the scenario discussed is to increase arts performances by 25 per cent, or to avoid a 25per cent or 50 per cent decrease in the number of performances. Among arts patron households, the mean WTP ranges from $61 to $132.Consumer demand for arts performances in large part follows a predictable pattern. The likelihood of respondents agreeing to make the donation that is requested rises as the size of the donation decreases. The likelihood is higher to avoid a 50 per cent decline in performances than to avoid a 25 percent decline in performances. The mean WTP rises with income, and arts patron households have a much higher WTP than all households. WTP rises with on-site use factors such as frequency of attendance. The WTP also rises for arts patrons households with off-site use such as watching arts events on television or reading about the arts in newspapers and magazines.  相似文献   
202.
Many educational and psychological tests are inherently multidimensional, meaning these tests measure two or more dimensions or constructs. The purpose of this module is to illustrate how test practitioners and researchers can apply multidimensional item response theory (MIRT) to understand better what their tests are measuring, how accurately the different composites of ability are being assessed, and how this information can be cycled back into the test development process. Procedures for conducting MIRT analyses–from obtaining evidence that the test is multidimensional, to modeling the test as multidimensional, to illustrating the properties of multidimensional items graphically-are described from both a theoretical and a substantive basis. This module also illustrates these procedures using data from a ninth-grade mathematics achievement test. It concludes with a discussion of future directions in MIRT research.  相似文献   
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Effects of competition, exercise, and mental stress on secretory immunity   总被引:2,自引:0,他引:2  
It has been suggested that the psychological stress associated with competitive sports events may help to explain the increased susceptibility to respiratory infections due to reductions in secretory immunity. In the current study, we investigated the influence of competitive exercise and psychological stress on secretory immunoglobulin A (s-IgA). Salivary s-IgA and heart rate were measured in 62 healthy young recreationally active men at rest and, in a between-subjects design, following one of four 8-min tasks: mental arithmetic, cycling at workloads of 60 to 180 W (mean = 146 W), mental arithmetic while cycling, or competitive cycling. Mental arithmetic was associated with significant increases in s-IgA concentration (mean = 49 microg.min(-1)) and s-IgA secretion rate (mean = 25 microg.ml(-1)) compared with rest, while mental arithmetic combined with exercise was associated with a significant increase in s-IgA concentration only (mean = 124 microg.min(-1)). In contrast, competitive exercise and exercise alone did not influence s-IgA concentration or secretion rate. Heart rate increased modestly to mental arithmetic (mean = 7 beats.min(-1)) and substantially, and similarly, to the three exercise tasks (mean = 56(62 beats.min(-1)). The hypothesis that the psychological stress of competitive exercise contributes to increased susceptibility to infection via reductions in s-IgA requires further investigation.  相似文献   
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The British Council is part of Britain's overseas representation and its aim is to promote a wider knowledge of Britain and the English language, and to develop closer cultural ties and better understanding between Britain and other nations. Thus it is concerned with cultural relations in the widest sense, embracing education, science and the arts, and it promotes all kinds of professional and intellectual interchange. In France, as elsewhere in Europe, the Council operates a number of programmes to facilitate these exchanges, and in this article — although it is naturally based on Anglo-French scientific exchanges — I hope to give an idea of the sort of schemes which are also available in other European countries.  相似文献   
209.
Willmott GR  Platt M  Lee GU 《Biomicrofluidics》2012,6(1):14103-1410315
Tunable pores (TPs) have been used for resistive pulse sensing of 1 μm superparamagnetic beads, both dispersed and within a magnetic field. Upon application of this field, magnetic supraparticle structures (SPSs) were observed. Onset of aggregation was most effectively indicated by an increase in the mean event magnitude, with data collected using an automated thresholding method. Simulations enabled discrimination between resistive pulses caused by dimers and individual particles. Distinct but time-correlated peaks were often observed, suggesting that SPSs became separated in pressure-driven flow focused at the pore constriction. The distinct properties of magnetophoretic and pressure-driven transport mechanisms can explain variations in the event rate when particles move through an asymmetric pore in either direction, with or without a magnetic field applied. Use of TPs for resistive pulse sensing holds potential for efficient, versatile analysis and measurement of nano- and microparticles, while magnetic beads and particle aggregation play important roles in many prospective biosensing applications.  相似文献   
210.
In this study a method for determining elbow extension and elbow abduction for a cricket bowling delivery was developed and assessed for Jenny Gunn who has hypermobility in both elbows and whose bowling action has been repeatedly queried by umpires. Bowling is a dynamic activity which is assessed visually in real time in a cricket match by an umpire. When the legality of a bowler's action is questioned by an umpire a quantitative analysis is undertaken using a marker based motion analysis system. This method of quantifying elbow extension should agree with a visual assessment of when the arm is "straight" and should minimise the effects of marker movement. A set of six markers on the bowling arm were used to calculate elbow angles. Differences of up to 1° for elbow extension and up to 2° for elbow abduction were found when angles calculated from the marker set for static straight arm trials were compared with measurements taken by a chartered sports physiotherapist. In addition comparison of elbow extension angles at ball release calculated from the markers during bowling trials with those measured from high speed video also showed good agreement with mean differences of 0°±2°.  相似文献   
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