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51.
In a second test of an arthropod saturation hypothesis, we analyzed if the on-campus Anthropology Research Facility (ARF) at the University of Tennessee, Knoxville, with its 20+ yr history of carcass enrichment, is comparable to non-enriched sites in community structure of predatory and parasitic arthropods that prey upon the sarcosaprophagous fauna. Over a 12-day period in June 1998, using pitfall traps and sweep nets, 10,065 predaceous, parasitic, and hematophagous (blood-feeding) arthropods were collected from freshly euthanized pigs (Sus scrofa L.) placed at ARF and at three surrounding sites various distances away (S2-S4). The community structure of these organisms was comparable in most paired-site tests with respect to species composition, colonization rates, and evenness of pitfall-trap abundances on a per carcass basis. Site differences were found in rarefaction tests of both sweep-net and pitfall-trap taxa and in tests of taxonomic evenness and ranked abundances of sweep-net samples. Despite these differences, no evidence was found that the predatory/parasitic fauna at ARF was impoverished with fewer but larger populations as a result of carcass enrichment. Comparison of the sarcosaprophagous and predatory/parasitic faunas revealed a tighter (and more predictable) linkage between carrion feeders (sarcosaprovores) and their carrion than between carrion feeders and their natural enemies (predators and parasitoids), leading us to conclude that ARF is more representative of surrounding sites with respect to the sarcosaprovore component than to the predatory/parasitic component within the larger carrion-arthropod community. 相似文献
52.
Analysis of carbohydrate-deficient transferrin (CDT) in vitreous humour as a forensic tool for detection of alcohol misuse 总被引:1,自引:0,他引:1
Analysis of carbohydrate-deficient transferrin concentration in vitreous humour (VH-CDT) has recently been demonstrated to be useful for diagnosis of pre-mortal alcohol misuse, but more knowledge considering possible methodological problems is warranted. In a forensic sample we examined the stability of VH-CDT during laboratory handling as well as the possible affection of time-dependent changes of total transferrin concentrations in vitreous humour (VH-Transferrin) in the dead body on VH-CDT as indicator of alcohol misuse. By use of a commercial assay designed for serum analysis (CDTect) it was possible to measure VH-CDT with high precision, and detectable amounts were found in 20 of 21 alcoholics and in two of seven controls. The compound was demonstrated to be stable in vitreous humour during laboratory handling, since the results of the first analysis were well reproducible after 4 months storage of the specimens (rs=0.86, P=0.0002). Transferrin concentrations in vitreous humour (VH-Transferrin) correlated to the estimated time since the individual last time had been alive before the forensic examination (rs=0.57, P<0.005). However, in this small sample the discriminating property of VH-CDT as indicator of alcohol misuse was not decisively affected, whether or not the variables "VH-Transferrin" and "estimated time since the individual last time had been alive" were considered in a multivariate logistic regression analysis (minor change in the beta-coefficient from 0.57 to 0.52, P=0.086). We conclude that CDT is stable in vitreous humour during proper laboratory handling and that detection of VH-CDT is primarily a marker of alcohol misuse before death. However, the results of this study do not exclude that time-dependent changes of VH-Transferrin, possibly affecting VH-CDT, may occur in the dead body. VH-CDT analysis should thus, at present, be restricted to cases with rather short post-mortal time interval. 相似文献
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Scholars of legislative studies typically use ideal point estimatesfrom scaling procedures to test theories of legislative politics.We contend that theory and methods may be better integratedby directly incorporating maintained and to be tested hypothesesin the statistical model used to estimate legislator preferences.In this view of theory and estimation, formal modeling (1) providesauxiliary assumptions that serve as constraints in the estimationprocess, and (2) generates testable predictions. The estimationand hypothesis testing procedure uses roll call data to evaluatethe validity of theoretically derived to be tested hypothesesin a world where maintained hypotheses are presumed true. Wearticulate the approach using the language of statistical inference(both frequentist and Bayesian). The approach is demonstratedin analyses of the well-studied Powell amendment to the federalaid-to-education bill in the 84th House and the Compromise of1790 in the 1st House. 相似文献
55.
Adam Crawford 《European Journal on Criminal Policy and Research》1999,7(4):509-530
This article casts a critical eye over some of the (often ignored) assumptions which underlie recent appeals to community in crime prevention and control. The article considers the philosophical origins, ambiguities and tensions within such appeals. In so doing, it draws explicitly upon the growth of community safety and to a lesser extent restorative justice in Britain and considers some of the implications to which this shift may give rise. In particular, it focuses upon the manner in which appeals to community converge and collide with changing social relations which may undermine their progressive potential. Specific attention is given to the implications of: increasing social and spatial dislocation; the commodification of security; and policy debates about a growing underclass. It is argued that there is much confusion as to how, and to what extent, communities can contribute to the construction of social order. Within the dynamics of community safety and crime control practices there are dangers that security differentials may become increasingly significant characteristics of wealth and status with implications for social exclusion. This questions the extent to which crime is an appropriate vehicle around which to (re)construct open and tolerant communities. 相似文献
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The “Science of Science Policy”: reflections on the important questions and the challenges they present 总被引:1,自引:1,他引:0
Adam B. Jaffe 《The Journal of Technology Transfer》2008,33(2):131-139
Developing the “Science of Science Policy” will require data collection and analysis related to the processes of innovation
and technological change, and the effects of government policy on those processes. There has been much work on these topics
in the last three decades, but there remain difficult problems of finding proxies for subtle concepts, endogeneity, distinguishing
private and social returns, untangling cumulative effects, measuring the impact of government programs in a true “but for”
sense, and sorting out national and global effects. I offer observations on how to think about these issues.
This paper was presented as the Keynote Address at the NSF Workshop on Advancing Measures of Innovation: Knowledge Flows,
Business Metrics, and Measurement Strategies, Arlington, VA, June 2006. 相似文献
59.
60.
The importance of “spillovers” in the policy mission of the advanced technology program 总被引:3,自引:0,他引:3
Adam B. Jaffe 《The Journal of Technology Transfer》1998,23(2):11-19
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