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Government policies like the Advanced Technology Program (“ATP”) are intended, at least in part, to remedy the “market failure” inherent in the fact that a significant portion of the social benefits of new knowledge and technology are not captured by a firm that invests in R&D. ATP’s project selection, and its evaluation of the impact of its program, can be made more effective by explicitly incorporating the analysis of such “spillovers.” For project selection, this means identifying technological, organizational and economic factors that tend to oint to a large “spillover gap,” or deviation between the social and private rates of return to a proposed project. For program evaluation and assessment, it means adapting existing study methods that measure social returns to innovation in ways that explicitly capture spillover effects. This paper is based on a study that I performed for the ATP, Economic Analysis of Research Spillovers: Implications for the Advanced Technology Program, NIST GCR 97-708. I have benefited from comments and useful discussions with Zvi Griliches, Jeanne Powell, Rosalie Ruegg, and Richard Spivack. Some of the ideas in this paper grew out of previous joint research with James Adams. The views expressed herein are my own, however, and should not be attributed to any of these individuals or to the ATP.  相似文献   
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Chloroquine concentrations in blood and tissues were examined in overdose and non-overdose cases to determine appropriate ranges for interpretation. Twenty-nine literature overdose cases and 8 non-overdose literature cases were compared with this laboratory's findings. The results indicate significant postmortem redistribution of chloroquine. Combining this laboratory's results and the literature results indicates that using a liver concentration of 150 mg/kg as a cutoff between overdose and non-overdose concentrations properly identified 30 of the 34 published cases containing liver chloroquine and 19 of the 20 presented cases.  相似文献   
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Power Dynamics in an Experimental Game   总被引:1,自引:1,他引:0  
We introduce a new experimental method for studying power. Drawing from multiple theoretical perspectives, we conceptualize power as relational and structural, as well as comprised of different forms through which basic human needs can be met. Thus, the method we introduce examines how, when faced with a particular need, people use multiple forms of power concurrently and within a “field of influence,” namely, the other players in a game. This enabled us to examine how one form of power is transformed into another and how power is transferred from one player to another through interaction, as well as to measure power as behavior, as the exercise of choice, as potential, and as outcomes. Two experiments using egalitarian start conditions and a survivable ecology demonstrated that participants used power to gain more power, creating inequality. Being the target of force made some players unable to “survive” in the local ecology. Theoretical and methodological issues in the study of power are discussed and the application of our game method to the study of power in other fields is considered.  相似文献   
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The recent formation of a United Kingdom and Irish working group, the Body Fluids Forum (BFF), highlighted the need to investigate different working practices prior to any inter-laboratory comparison work and identification of best practice. Various dilutions of semen were seeded onto swabs and cloth samples for each BFF member laboratory to test using their standard techniques. The results showed that the detection of acid phosphatase on swabs is best achieved using direct testing rather than on an extract from the swab. Extraction methods for spermatozoa require a balance to be achieved between using a sufficient volume of water to ensure optimal release and minimal volume to ensure a concentrated extract. PSA tests were investigated and found to be more sensitive than Choline. DNA profiles were obtained from samples in which no spermatozoa had been detected during microscopic examination.  相似文献   
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Healthy men, 20 to 60 years old, drank a moderate dose of ethanol in the morning after an overnight fast. They consumed either neat whisky in amounts corresponding to 0.34, 0.51, 0.68, 0.85, or 1.02 g of ethanol per kilogram of body weight or 0.80 g/kg ethanol solvent diluted with orange juice. The peak blood-ethanol concentration (BEC) increased with the dose administered, but the time required to reach the peak was not markedly influenced over the range of doses studied. At a dose of 0.68 g/kg, the peak BEC ranged from 52 to 136 mg/dL (N = 83), and slow absorption (a late-occurring peak) produced a lower peak BEC. The peak BEC was reached between 0 and 45 min for 77% of the subjects (N = 152) and between 0 and 75 min for 97% of them. The time of peaking in venous blood occurred, on average, 10 min later than in capillary (fingertip) blood although the peak BEC was not appreciably different; the mean venous BEC was 97.0 mg/dL (range, 76 to 112 mg/dL), and the mean capillary BEC was 99.6 mg/dL (range, 75 to 123 mg/dL). When subjects drank 0.80 g/kg ethanol diluted with orange juice over 30 min, the average BEC increment between the end of drinking and the peak was 33 mg/dL (range, 0 to 58 mg/dL). The rate of absorption of ethanol was 1.78 mg/dL/min (range, 0.52 to 4.8 mg/dL/min), and the peak BEC occurred within 60 min after the end of drinking in 92% of the trials. The largest BEC increment (mean, 21 mg/dL; range, 0 to 44 mg/dL) was seen during the first 15 min after the drinking period.  相似文献   
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